A holistic take on the Ikazuchi

[Jefffar]

Shadowlogan, if the Alpha is truely a spacecraft it will have manoeuvring thrusters that can provide the impulse needed.

[Arnie100]

I always wondered HOW a Garfish recovered its fighters...

[Jefffar]

Almost wondering if there is some sort of automated landing system that guides the fighter through the requisite manoeuvres once it reaches a predetermined position and velocity relative the ship.


That or a tractor beam.

[Seto Kaiba]

Shadowlogan, if the Alpha is truely a spacecraft it will have manoeuvring thrusters that can provide the impulse needed.

ShadowLogan's point isn't that there aren't verniers on the Alpha's airframe for maneuvering in space... the point he's making is that official canon spec for the VF/A-6 in Robotech says the fighter's small size resulted in a comparatively modest onboard propellant capacity that gives it low endurance in space operations. Trying to land back down the same launch tunnel the fighter launched from is an extremely high-precision approach to recovery, which would have consequences that would be felt in terms of greater propellant consumption during recovery. The Alphas also use their own engines, rather than a catapult, to launch on the pre-retrofit Ikazuchi-class (presumably catapult-assisted on the post-retrofit type), which is also propellant-intensive. This isn't really an issue when the fighters are being deployed directly into orbit for a reentry operation (minimal propellant required there), but as a space dogfighter that would pose a significant problem...

The Alpha is also never shown to be capable of the kind of lateral movement on vernier power that would be required for the perpendicular approach... which would also be propellant-intensive.

(The Alpha's stated low endurance in space is a matter of some debate between ShadowLogan and myself, given that some of the artistic license taken in RTSC can be taken to imply that the Alpha's engines are much more powerful than stated if taken literally instead.)

I always wondered HOW a Garfish recovered its fighters...

MOSPEADA's creators never did stop to consider how these ships might recover aircraft... they were never going to in the original plot, so presumably it just never came up.

[Jefffar]

Short legs is a relative term as we at least on one occasion see Alphas conduct a recon mission that appears to travwrse from the moon to the orbital debris field just above the earth and back again including performing such manoeuvres as hiding motionless within the debris.

That they were able to take cover in the debris (which is moving because it is in orbit) shows that they are, in theory at least, capable of some kind of docking manouvre.

[Seto Kaiba]

Short legs is a relative term as we at least on one occasion see Alphas conduct a recon mission that appears to travwrse from the moon to the orbital debris field just above the earth and back again including performing such manoeuvres as hiding motionless within the debris.

Yeah, that's the bit that's the artistic license... the first episode of the canceled Shadow Chronicles OVA depicts Earth's moon as being much, MUCH closer to Earth than it is in reality. The way it's drawn, it looks like the moon is only a few thousand kilometers from Earth instead of over a light second away, and the Shadow Fighters are shown getting from the moon to Earth orbit in just a handful of minutes instead of the 128 hours (about 5 1/3 days) it would take at the Shadow Fighter's listed top speed over the real world 384,400km distance. The evaluation of the physics involved by ShadowLogan, which I've reviewed and found no issues with, also points to the fact that the Shadow Fighter would be categorically incapable of the acceleration necessary to make the trip from the Moon to Earth (let alone back again) considering that it canonically is incapable of producing enough acceleration to reach the edge of space over an Earth-type planet. IIRC at one point one of us did the math and concluded that, to produce that kind of acceleration, the propellant would have to be coming out of the Alpha's engine nozzles at faster than the speed of light to produce the requisite acceleration with the volume available.

(See Conveniently Close Planet.)

In short, there's a fair amount of dramatic license in play in that scene because the flight depicted is several different kinds of impossible with the official spec for the VF/A-6 series... including the ones published in the Shadow Chronicles artbook. Harmony Gold's official policy for this kind of thing is to give primacy to the TV series material, which as noted above would make that one scene several different kinds of wrong.

That they were able to take cover in the debris (which is moving because it is in orbit) shows that they are, in theory at least, capable of some kind of docking manouvre.

Yeah, they had to switch to Guardian mode to do that, which the bays on the Ikazuchi post-retrofit type are too small to make workable.

There's also a slight problem in that the animators forgot the Shadow Fighter has no ventral engines to provide forward thrust in Guardian mode... which makes some of the maneuvers they were performing ALSO impossible.

(You'd almost swear it was a low-budget direct-to-video movie with all the quality issues that stereotypically entails...)

[Jefffar]

So you're agreeing we see the Alpha perform.feats on screen that don't fit the description of a short legged fighter of limited capabilities.

Robotech isn't exactly what one would call a hard sci-fi. The capabilities of any of the mecha at any point in the series are more subject to writer and animators fiat than strict adherence to the rules of physics.

We don't need an equation to justify the Alpha can do these things because we see them do it.

[Seto Kaiba]

So you're agreeing we see the Alpha perform.feats on screen that don't fit the description of a short legged fighter of limited capabilities.

Not quite. What I'm saying is that the first episode of the canceled Shadow Chronicles OVA shows something that cannot be taken at face value because of significant, canon-defying dramatic license in play... on top of a number of other problems with it.

Robotech isn't exactly what one would call a hard sci-fi. The capabilities of any of the mecha at any point in the series are more subject to writer and animators fiat than strict adherence to the rules of physics.

Granted, Robotech is not hard sci-fi... but it isn't an anything-goes fanfic that completely ignores physics either. This isn't a Super Robot series with New Powers as the Plot Demands, this is a "real robot" series where the mecha have officially-defined capabilities that were the basis for the animation of the mecha in the original works. Based on the official statements from Harmony Gold's creative staff, this is clearly a lapse in the name of dramatic license and not a faithful representation of the mecha's actual capabilities. Harmony Gold's official, canon position WRT VF/A-6 capabilities is that it's incapable of even suborbital flight unassisted and its small onboard fuel supply greatly limits its range in space.

We don't need an equation to justify the Alpha can do these things because we see them do it.

Based on Harmony Gold's official policy for conflicts between original series canon and subsequent works, we don't need to treat this scene as valid because it violates original series canon.

[Jefffar]

Nothing in that statement disproves that we see the Alpha perform manoeuvres on screen very similar to what it would be required to do during the recovery of an Alpha fighter aboard an Ikazuchi.

We don't see what the final step is, or know exactly where on the Ikazuchi that it gets recovered. But we can say the Alpha is shown to be able to do its part in the dance.

[Seto Kaiba]

Nothing in that statement disproves that we see the Alpha perform manoeuvres on screen very similar to what it would be required to do during the recovery of an Alpha fighter aboard an Ikazuchi.

Took me a sec to figure out where you were going with that... but, as I noted earlier, the problem with that line of reasoning is the maneuvers used to hide in the wreckage of a ship entailed using Guardian mode. The launch tunnels that we're speculating would also be used in recovery are just barely large enough to permit the fighter mode with a clearance of only a few centimeters on all sides.

(With a larger target, like the hypothetical front bay door mentioned earlier, I'd expect they'd just cruise in in fighter mode and let artificial gravity and possibly an arresting wire finish the job like they were shown doing when landing at Moon Base ALuCE immediately after taking cover in the orbital debris field.)

We don't see what the final step is, or know exactly where on the Ikazuchi that it gets recovered. But we can say the Alpha is shown to be able to do its part in the dance.

We can't say if that's true or not, because there's no statement at any level of clarity regarding how the Ikazuchi-class actually recovers its fighters.

One would assume, logically speaking, that they would favor the method that had the largest possible safety margins and required the least propellant expenditure on the part of the returning VF as a matter of logistical common sense. (Which would be all the more important when the standard fighter is acknowledged to have a very limited onboard propellant capacity, which would very likely be greatly depleted after combat maneuvers in space. This should, of course, be broadly true for all VFs and ships in the series... though the only one I can get into the nitty-gritty math on would be the VF-1, as it's the only one where the original creators went into that much detail.)

[Bamse]

LeElf on Deviant Art has an interesting theory on Ikazuchis recovering Alphas involving the dorsal bay folding out Daedalus-style to make a runway. Really quite ingenious.

[Jefffar]

I'm not saying the Alpha landed in Guardian, just that the Guardian modes manoeuvrability is up to the task of positioning itself prior to landing.

English also have nothing confirming that the Alpha event back in the tube/bunker directly when it landed. We have nothing conclusively telling us how the aircraft were handled aboard ship. Having them fly back into the tubes is just assumption and conjecture.

Remember that there was a point in time where Naval aviation meant landing your seaplane in the water next to your ship and then being lifted aboard by a crane. There's nothing saying the Ikazuchi is a passive part of the landing operation.

[ShadowLogan]

That's why I suspect the notion that they're ready for another Zentradi attack is misleading... they know from Exedore that the Zentradi are all but wiped out, and the only thing they're likely to encounter might be a few stragglers who could be overpowered with inferior ships using the same numerical superiority tactics that are the UEEF's stock in trade. They're ready for what they'd be able to reasonably expect from what's left of the Zentradi, not what the Zentradi could bring when they were still a functioning military.

I agree the UEDF:ASC wasn't prepared to deal with a Zentreadi level threat that approached Imperial-class fleet or larger (1million ships or more), and would have been geared more toward smaller scale actions. How small I don't think we can say, but given the statement about the Tri-Star's capability in the Infopedia such a conflict it would appear to be 1:1 (though it should be noted the Tri-Star doesn't exactly qualify what Zentreadi ship types it would hold its own against alone, it could be the Scout for all we know and need assistance to deal with the bigger ships).

The "recovery trapeze" approach may work for the pre-retrofit model, given that the machinery for it would fit neatly into the spacers between columns of Alphas.

Which is shown to be empty IIRC. I suppose the gantry's might extend outward. But I would suspect that if they are battloid mode they could land on the general hull and "walk" themselves into the slot faster and easier than lining up for a trapeze or crane if we are talking multiple recoveries.

Shadowlogan, if the Alpha is truely a spacecraft it will have manoeuvring thrusters that can provide the impulse needed.

Seto pretty much has it covered. I'm just going to add We never see the Alpha in F mode move like a spacecraft should, it moves like an aircraft.

The Alphas also use their own engines, rather than a catapult, to launch on the pre-retrofit Ikazuchi-class (presumably catapult-assisted on the post-retrofit type), which is also propellant-intensive.

I would not rule out what amounts to a "catapult" for the Series Ik to launch the Battloid, though there is nothing to suggest AFAIK that it is the case.

IIRC at one point one of us did the math and concluded that, to produce that kind of acceleration, the propellant would have to be coming out of the Alpha's engine nozzles at faster than the speed of light to produce the requisite acceleration with the volume available.

I did the math, it showed that the 16 PC canisters worth of material for the Palladium listed endurance at full thrust could not work without the exhaust material being faster than the speed of light (which matter can not travel at). That requires the Alpha (and Beta) to use something else for propellant (either in part or full) that is not in those 16 PC canisters.

There's also a slight problem in that the animators forgot the Shadow Fighter has no ventral engines to provide forward thrust in Guardian mode... which makes some of the maneuvers they were performing ALSO impossible.

While the Alpha to Shadow version is stated to drop the VTOL engines, and said engine (groin/rear) rotates between F/B and G modes, nothing prevents the Shadow Fighter from having a fixed engine in that location per say. Though such an engine would have to operate without apparent nozzle or large "give away" opening (possible IINM) given a need to keep it visually a match for the series, but text doesn't indicate an engine of this type was installed.

So you're agreeing we see the Alpha perform.feats on screen that don't fit the description of a short legged fighter of limited capabilities.

The Problem is if we take that to the logical conclusion with depictions (as part of a single flight) will result in the Alpha family (or just the Shadow model) being able to perform manoeuvres that we are specifically told it can not do (get into orbit on its own power), and require some wrangling to justify the Beta Fighter's relationship with the Alpha. As mentioned Seto and I have had this discussion numerous times in the past, both here and at RT.com (one of which IINM spawned the Alpha entry getting a revision in the Infopedia that put into place the makes no sense "lack of suborbital altitude" capability).

The series/OVAs show one thing, but the outside supporting material says the opposite. This isn't the only case in RT either of this happening.

I always wondered HOW a Garfish recovered its fighters...

While not depicted the most likely explanation is similar to how the ASC's various cruisers operated that had similar fighter bays facing to the front, or the Garfish "scooped" them up by coming up from behind (or from front, but then you have to be able to turn them around so they can launch again).

[glitterboy2098]

i would point out that the shadow alpha's we see maneuvering in Guardian mode are in space, under orbital microgravity conditions. under such conditions the standard maneuvering thrusters should be sufficient.

the Shadow Alpha's and Shadow Drones we see in the show proper only appear in Fighter and Battloid mode, with the fighter mode not performing any maneuvers requiring VTOL ability, and the Battloid mode showing VTOL flight but having access to the leg thrusters and in the case of the Drones, an extra thruster replacing the head.


Garfish recovery is fairly simple.. the garfish coasts along, the alpha maneuvers in front of it, coasting along at the same speed while getting into position, then uses its thrusters to slow down a small amount to allow the garfish to overtake it at a relative crawl.

this scene from Gundam 0081 is probably the best example i can find of the method, though it (rather dangerously) uses that method in an atmosphere (where the need for wings to provide lift would make the final moments inside the hanger rather a difficult piloting job.. even if the Optical landing System had functioned properly.)


and Seto does have a point about the Galactica style bays.. being able to approach from the rear for a velocity matching landing would make it easier to do (and with the Galactica's outrigger pods, could even be done while under some degree of thrust by the carrier), the fact that you cannot easily "wave off" would require a greater degree of skill, especially during combat landings where your trying to minimize the time spent in the landing pattern. presumably in the BSG universe they opted for protection of the landing deck and fighters over ease of landing. (and exposed landing deck would be much easier for the Cylon forces to attack with their Raiders and Missiles, crippling the Colonial Force's airwings. the pods might be trickier to land in, but they put the landing fighters behind enough armor to block strafing runs and as we see in the pilot, direct nuclear strikes.)

though it is likely that outside of combat, the Garfish, Ikazuchi, and other ships of robotech would have the same thing they do in BSG (and are close to deploying IRL).. an automatic landing system that connects the plane via radio network to the ship and allows hands free safe landings. though the Galactica itself disabled such a system for its own reasons..

[Seto Kaiba]

LeElf on Deviant Art has an interesting theory on Ikazuchis recovering Alphas involving the dorsal bay folding out Daedalus-style to make a runway. Really quite ingenious.

Ventral, it was the large, unexplained bulge on the lower hull.

I'm not saying the Alpha landed in Guardian, just that the Guardian modes manoeuvrability is up to the task of positioning itself prior to landing.

That would work if it were landing on a large, flat surface... but for something like the proposed recovery-via-launch-tube the transformation will throw off the positioning of the fighter. (Newton's third law in action.)

English also have nothing confirming that the Alpha event back in the tube/bunker directly when it landed. We have nothing conclusively telling us how the aircraft were handled aboard ship. Having them fly back into the tubes is just assumption and conjecture.

That was the idea that was under discussion when we diverged into the discussion of the VF/A-6's propellant capacity.

Also, you're just restating what I said in my previous post.

Remember that there was a point in time where Naval aviation meant landing your seaplane in the water next to your ship and then being lifted aboard by a crane. There's nothing saying the Ikazuchi is a passive part of the landing operation.

There's no evidence for any of the ships employing active recovery methods like the launch arms of the ARMD-class space carriers that appeared for the first time in Macross: Do You Remember Love?.

How small I don't think we can say, but given the statement about the Tri-Star's capability in the Infopedia such a conflict it would appear to be 1:1 (though it should be noted the Tri-Star doesn't exactly qualify what Zentreadi ship types it would hold its own against alone, it could be the Scout for all we know and need assistance to deal with the bigger ships).

It'd be so much easier to be clear about this if they properly quantified the alleged benchmarking, wouldn't it? For all we know, the estimate was done assuming the ship had reflex warheads, which it doesn't actually employ normally.

Which is shown to be empty IIRC. I suppose the gantry's might extend outward. But I would suspect that if they are battloid mode they could land on the general hull and "walk" themselves into the slot faster and easier than lining up for a trapeze or crane if we are talking multiple recoveries.

There's kind of a "wall" between columns, so the equipment may fold into that. (There's only really one good piece of art for it though, so it's hard to say.)

Seto pretty much has it covered. I'm just going to add We never see the Alpha in F mode move like a spacecraft should, it moves like an aircraft.

To be completely fair, the same can be said for every other VF in the series... it's a fairly common trope. Even Macross barely pays more than lip service to realistic space maneuvering outside of higher-budget feature films most of the time.

While the Alpha to Shadow version is stated to drop the VTOL engines, and said engine (groin/rear) rotates between F/B and G modes, nothing prevents the Shadow Fighter from having a fixed engine in that location per say.

The absence of a visible engine would tend to be a bit of a problem... though IIRC the Shadow Fighter entry does mention those engines being out-and-out removed.

(one of which IINM spawned the Alpha entry getting a revision in the Infopedia that put into place the makes no sense "lack of suborbital altitude" capability).

Tommy only paid attention to the bits that were OSM-driven... hence the bit about the VF-1 being able to independently achieve LEO, and the Legioss (Alpha) having an atmospheric service ceiling well below the edge of space (~18km, if memory serves). If he'd paid attention to the rest, the Infopedia could probably have got a decent upgrade out of it.

[glitterboy2098]

the complaints about the alpha and it's orbital travels is false though. you can have the Delta-V for trans lunar trips, but still lack the thrust levels required to reach orbit. look at the Saturn V. the third stage had enough Delta-V to put the Command/Service Module onto a trans-lunar orbit.. but it would be unable to boost said module into low earth orbit on its own, requiring the first two stages.

in space travel, a long slow burn with a lower thrust engine is actually more efficient in terms of Delta-V than a short energetic one by a high thrust engine. the higher the thrust levels, the more wasteful of energy and reaction mass the engine tends to be.

and since an Alpha's remass would be separate from the fuel for it's power supply, it can easily spend long periods coasting on it's transfer orbit.. which means the Delta-V requirement for the trip can be lower.

[ShadowLogan]

The absence of a visible engine would tend to be a bit of a problem... though IIRC the Shadow Fighter entry does mention those engines being out-and-out removed.

The Shadow Fighter is mentioned to drop the VTOL engines yes, but it doesn't say they are replaced with a non-VTOL engine in either bay. However there are a few propulsion engine options that might work with the visuals, but the use of said engine types* would be pure speculation at this point given the supporting material.

*You have Lightcraft and its microwave variant (and maybe others operate similarly) but they require some ejection method for the propellant, something akin to an aerospike engine (but without the noticeable spike for obvious reasons). They are just engines that I can think of with out a traditional noticeable nozzle and would create exhaust (though IINM distinct exhaust incompatible with the visuals). The alternative is a conventional nozzle that can "hide" and "deploy" as needed (either by memory materials or hatch) with a fixed position engine (one that doesn't rotate like the stock Alpha does.

the complaints about the alpha and it's orbital travels is false though. you can have the Delta-V for trans lunar trips, but still lack the thrust levels required to reach orbit. look at the Saturn V. the third stage had enough Delta-V to put the Command/Service Module onto a trans-lunar orbit.. but it would be unable to boost said module into low earth orbit on its own, requiring the first two stages.

True thrust is a potential pit-fall, but if one is using the OSM specs the Alpha does have enough thrust (even if we ignore the OSM spec, the official line is the Alpha has a high-thrust to weight ratio which can be taken to be greater than 1).

in space travel, a long slow burn with a lower thrust engine is actually more efficient in terms of Delta-V than a short energetic one by a high thrust engine. the higher the thrust levels, the more wasteful of energy and reaction mass the engine tends to be.

This is only true under certain circumstances, most of which are near term applicable systems. Specific Impulse is the measure of efficiency, and a fusion based system would allow high thrust and Specific Impulse for example.

[Seto Kaiba]

the complaints about the alpha and it's orbital travels is false though. you can have the Delta-V for trans lunar trips, but still lack the thrust levels required to reach orbit.

Only in the most general sense... the problem that you're missing is that the Alpha's engines aren't going to be able to operate in their air-breathing mode all the way to Low Earth Orbit. Above a certain altitude, the fighter is going to have to transition to running its engines in space mode and consuming propellant to continue its ascent. If it doesn't have enough propellant stored onboard to produce a sufficient delta-v to get to the edge of space even temporarily, let alone achieving a stable low Earth orbital flight path, it almost certainly doesn't have the delta-v to for a translunar trip at all... let alone in a reasonable timeframe or making a round trip.

in space travel, a long slow burn with a lower thrust engine is actually more efficient in terms of Delta-V than a short energetic one by a high thrust engine. the higher the thrust levels, the more wasteful of energy and reaction mass the engine tends to be.

This is true, but its relevance is superficial at best given that we're not talking about an unmanned probe making the trip in a matter of weeks... but rather a manned spacecraft making the trip a lot faster.

The Shadow Fighter is mentioned to drop the VTOL engines yes, but it doesn't say they are replaced with a non-VTOL engine in either bay. However there are a few propulsion engine options that might work with the visuals, but the use of said engine types* would be pure speculation at this point given the supporting material.

With nothing said WRT replacement of the removed engines, the safest assumption is that there was no replacement for those engines...

True thrust is a potential pit-fall, but if one is using the OSM specs the Alpha does have enough thrust (even if we ignore the OSM spec, the official line is the Alpha has a high-thrust to weight ratio which can be taken to be greater than 1).

Back-of-the-envelope math puts the T/W ratio at around 1.724[sup]1[/sup], but as noted above raw maximum thrust only counts as long as your propellant holds out or you're low enough in the atmosphere that you can use intake air as propellant. The Alpha's problem is, as Harmony Gold itself notes, a matter of insufficient propellant. (Remedied, as they note, by the addition of the Beta and its sizable onboard fuel tanks.)


1. I had to edit this post when I noticed I'd inadvertently done the math using the OSM engine setup, not the Robotech one where two of the sub-engines are permanently mounted in the underside instead of in the legs alongside the main nozzles with two bypass nozzles in the underside. This drops the T/W ratio from ~2.3 to 1.724, which is still quite high by modern standards.

[glitterboy2098]

my point is that just because it has the Delta-V is sufficent for translunar travel has no bearing on whether it can go from ground to orbit.

an ion drive can be built with enough delta-V to reach the moon (or mars, or even freaking pluto) but because the thrust is so low, it would be unable to get to orbit.
it is more than just the Delta-V when it comes to getting to orbit, it is also a factor of having enough thrust (and thus acceleration) to overcome both air drag and the pull of gravity. once in orbit and freefall, very small thrusts can be used because your not having to fight against gravity in the same way, not having to use your thrust to stay up in the air at the same time you are trying to accelerate up to speed.


and as far as thrust to weight ratio's.. that is actually what i am speaking of. ok so an alpha has a ratio greater than 1. so does the F-15.

in order to be able to reach orbit, a rocket requires a T/W ratio greater than 2, but to do it without burning a crapload of fuel and taking forever, it needs a 3+. most IRL generate 10+
the Saturn V first stage alone had a ratio of almost 100+ (though in practice, this was rather lower as this ratio did not include the mass of the 2nd, 3rd, and Command-service module it was launching)

all a T/W ratio above 1 allows you do do is climb vertically without losing velocity. the F-15 has a ratio of 1.07. the Eurofighter typhoon has one of the highest for a jet, at 1.15 when configured as an interceptor (minimal external stores). it does not really have much of a performance gain over the F-15 in a vertical envelope. the space shuttle has a T/W ratio of around 3 when running with the external tank. (when it jettisons, it throttles down to around a 1.5 to get the most out of the limited onboard fuel.)
the X-15 had a T/W ratio of 2.04, explaining how it could go sub-orbital.. it just lacked enough fuel (and thus delta-V) to reach stable orbit.

(and btw.. T/W has only limited bearing on atmospheric speeds.. the F-15 has a 1.07 and can hit mach 1.2 at low altitude and 2.5 at high. the SR-71 though only had a 0.44 but could hit mach 3.3+ at high altitude..)


i can easily see the VF-1 having a ratio of over 3. fusion rockets are enormously powerful. the main reason it would be limited once it got up there would just be fuel.. since it uses the same fuel for remass and reactor fuel (and the same engines as rockets and powersupply), by the time it reaches low orbit it would have drained most of its fuel for use as remass, and wouldn't be able to do much else without running out of power. (thus the advent of the booster rocket system to get it up there without using its own internal fuel.)

the Alpha on the otherhand might well just have more efficient engines (probably plasma, given the fluff for other PC powered mecha) making the best use of the limited remass tankageonboard*. lower thrust (and thus lower atmospheric speeds and no ability to get to orbit) but decent Delta-V. it just takes longer to effect an orbital change.

*not really has a lot of room for it, being smaller and having missile launchers packed in everywhere other mecha might fit a fuel tank.

[Seto Kaiba]

my point is that just because it has the Delta-V is sufficent for translunar travel has no bearing on whether it can go from ground to orbit.

No, we know what your point was... the problem is, as ShadowLogan and I noted, your premise doesn't check out and you've built it on a false parallel to low-thrust, low-velocity, long-duration ion propulsion transits which start from a point outside the high delta-v orbital transitions thanks to having been launched by a separate high delta-v rocket system.

(This would be analogous to claiming the Alpha could make the flight to the moon unassisted by failing to account for the contribution of a Beta fighter providing a significant amount of acceleration already while ferrying it up to a high orbital transition.)

i can easily see the VF-1 having a ratio of over 3. fusion rockets are enormously powerful. the main reason it would be limited once it got up there would just be fuel.. since it uses the same fuel for remass and reactor fuel (and the same engines as rockets and powersupply), by the time it reaches low orbit it would have drained most of its fuel for use as remass, and wouldn't be able to do much else without running out of power. (thus the advent of the booster rocket system to get it up there without using its own internal fuel.)

3.47, without any additional bolt-on conformal tanks, boosters, etc. This part of your summation is largely accurate, being the reason the VF-1 employs a surface-to-orbit booster system even though it's technically capable of a flight ceiling in low Earth orbit on internal propellant only and why for space flight the VF-1 commonly employs that FAST pack that adds both hybrid rocket boosters to reduce main engine propellant consumption and conformal tanks to increase its onboard fuel capacity to not quite 5 times what the fighter carries in its atmospheric configuration.

(It's worth noting that OSM spec indicates the reactor fuel consumption in space is only high when the engines are producing thrust... at idle, their consumption is no worse than in atmosphere.)

the Alpha on the otherhand might well just have more efficient engines (probably plasma, given the fluff for other PC powered mecha) making the best use of the limited remass tankageonboard*. lower thrust (and thus lower atmospheric speeds and no ability to get to orbit) but decent Delta-V. it just takes longer to effect an orbital change.

As noted previously, the limited delta-v is also a factor in the inability to reach even the edge of space... because the edge of space is well above the altitudes where the fighter's engines would be able to operate in air-breathing mode, and would thus be dependent on the internal propellant stores. With the official spec stating the Alpha's propellant tank limitations result in it having very limited range in space, that would tend to argue against the idea that they've got great range but rubbish acceleration...

*not really has a lot of room for it, being smaller and having missile launchers packed in everywhere other mecha might fit a fuel tank.

Best-guess estimations based on known voids in the structure put the Alpha's onboard propellant tank capacity at around 1/4th to 1/5th the VF-1's, around 280-350L. Considering it wasn't really designed to be a space dogfighter, that's not really anything to complain about IMO. For what it was designed to do, that's probably enough to get the job done... extended carrier operations just aren't what it was designed to do (probably why, when they conceived the Super Shadow Fighter as a space dogfighter, the first thing they did was bolt extra fuel tanks and boosters to it, then make the Beta mandatory.)

[ShadowLogan]

With nothing said WRT replacement of the removed engines, the safest assumption is that there was no replacement for those engines...

I agree that would be the safe assumption that we treat it as an Animation Error until HG says otherwise, but it is not necessarily the only option (HG could "clarify" the issue after all, I'm not holding by breath for that to happen anytime soon though).

Back-of-the-envelope math puts the T/W ratio at around 1.7241, but as noted above raw maximum thrust only counts as long as your propellant holds out or you're low enough in the atmosphere that you can use intake air as propellant. The Alpha's problem is, as Harmony Gold itself notes, a matter of insufficient propellant. (Remedied, as they note, by the addition of the Beta and its sizable onboard fuel tanks.)

I agree you need the propellant load. But the effectiveness of that propellant load will be determined by the efficiency of the drive (or more accurately how fast it expels said material, which impacts: thrust, delta-V, and specific impulse/efficiency). HG could always give the Alpha a "late model" engine upgrade explaining the difference (IINM all the Alpha models in question that support the notion of high Delta-V are Shadow versions in depictions)

And as noted, TSC's Wolf Recon depiction (assuming Apollo trip time and not something more energetic/shorter) flies in the face of that statement as the major maneuvers quickly add-up to showing the required Delta-V (and thus propellant load). The series itself doesn't provide anything like logical flight equal to Wolf Recon, but it does suggest that Sub-Orbital flight (minimum) is possible under its own power and comparing it to real-world systems.

What should be done at this point is to take HG's Alpha statement as a general blanket statement, but amend it to allow for limited (earth) orbital flight within certain parameters (which the footage suggest, and a restriction I don't object to) and suborbital flight is possible (suborbital altitude to me is more of a non-sense phrase, you can be at an orbital altitude, but still not have sufficient velocity to be in orbit at said altitude which makes one suborbital by default). What the Beta would allow is a much wider operating parameters before requiring refuelling (among other things).

my point is that just because it has the Delta-V is sufficent for translunar travel has no bearing on whether it can go from ground to orbit.

That is true that the Delta-V needs to be coupled with sufficient thrust for certain missions, but that can be shown to not be an issue here because there is nothing to indicate the Alpha's space engines are low thrust (its flying around and launching from the surface of the Moon in Ep83) or have the option to switch to such a mode. So any Delta-V to be estimated from footage can be shown to have sufficient thrust by default.

an ion drive can be built with enough delta-V to reach the moon (or mars, or even freaking pluto) but because the thrust is so low, it would be unable to get to orbit.

If you have a sufficiently light enough and powerful enough energy source for the Ion Drive you could theoretically get into orbit. The main drawback is getting such a light and powerful energy source for it to be practical is not possible in the real world (currently or projected) as you add a more massive power source for diminishing gains in output. Weather such a restriction would apply to RT (or the OSMs) isn't known (AFAIK), they could have light enough power plants to allow for these systems to exist in "high thrust states" then again they might not.

[Seto Kaiba]

I agree that would be the safe assumption that we treat it as an Animation Error until HG says otherwise, but it is not necessarily the only option (HG could "clarify" the issue after all, I'm not holding by breath for that to happen anytime soon though).

I'll draft an e-mail to Tommy tonight... but I'm not optimistic we'll see a response. Ever since Academy bombed on Kickstarter, the HG "powers that be" seem to be thoroughly disinterested in anything to do with Robotech's animated series. It's all about the merchandise lines they've picked up from the Macross bootleggers in Hong Kong and the Macross Saga comics now.

And as noted, TSC's Wolf Recon depiction (assuming Apollo trip time and not something more energetic/shorter) flies in the face of that statement as the major maneuvers quickly add-up to showing the required Delta-V (and thus propellant load). The series itself doesn't provide anything like logical flight equal to Wolf Recon, but it does suggest that Sub-Orbital flight (minimum) is possible under its own power and comparing it to real-world systems.

That the maneuvers the Wolf Squadron recon detachment is depicted doing don't tally with any previous depiction of the VF/A-6 platform or official documentation regarding its performance is a pretty clear indicator that the OVA's staff dropped the ball... especially since they had already taken a fair amount of artistic license with the proximity of Earth to Luna.

Logically, we would've expected there to be a ship somewhere just offscreen that ferried them into the area and recovered them to return to ALuCE base, given that the series depicts the Beta (and its capacious fuel tanks) as a necessary addition to the Alpha in order to make a one way trip from Luna to Earth... a much more forgiving course in terms of delta-v budget than going the other way. If the Alpha were capable of making the one-way trip in any reasonable timeframe, there wouldn't have been any reason for the UEEF to send so many Ikazuchi-class and Garfish-class ships to ferry them directly to Earth's orbit. Especially glaring given how vulnerable those ships are... and the operating profile we're told applied to both the UEDF/ASC and UEEF carriers. These aren't long-range, high-endurance space fighters meant for long-range cruises or patrols... they're short-ranged fighters meant to be launched from a carrier in close proximity to an enemy ship or planet. They didn't really need long-range cruise capability, because they had fold-capable ships to ferry them directly to the target.

What should be done at this point is to take HG's Alpha statement as a general blanket statement, but amend it to allow for limited (earth) orbital flight within certain parameters (which the footage suggest, and a restriction I don't object to) and suborbital flight is possible (suborbital altitude to me is more of a non-sense phrase, you can be at an orbital altitude, but still not have sufficient velocity to be in orbit at said altitude which makes one suborbital by default). What the Beta would allow is a much wider operating parameters before requiring refuelling (among other things).

Had Harmony Gold not explicitly repeated, and then doubled down on, the statement that the VF/A-6 series is incapable of achieving even a suborbital flight path and has very limited range in space because of its modest onboard propellant capacity, I might agree. But they did go and repeat all those statements, and the existence of the Super Shadow Fighter as the upgrade in the film also argues against it, given that they apparently felt it necessary to make the Beta mandatory and add FAST packs to turn the Shadow Fighter into an effective space fighter.

The only interpretation I can reach based on the available evidence is that it really is just a gaffe on the part of the OVA's production team... or, if we're being charitable, a case of artistic license in physics or astrophysics.

[Jefffar]

Short legs in space is a relative term.

Remember the OSM had the Horizontal etc attacking from Mars. The Alpha's short range may be that it can't make this trip on its own (hence the carrier craft). Getting from Earth to the Moon is a very small fraction of this distance.

[Seto Kaiba]

Short legs in space is a relative term

Granted, but they play up the "limited range" part in AotSC and the inability of the craft to even reach the edge of space over an Earth-type planet kinda kills your premise.

Remember the OSM had the Horizontal etc attacking from Mars. The Alpha's short range may be that it can't make this trip on its own (hence the carrier craft). Getting from Earth to the Moon is a very small fraction of this distance.

No, the OSM didn't have that... that's a common misconception among Robotech fans.

The troops from Mars and Jupiter who were mustered for the Earth Recapture operations gathered at a pre-invasion staging area on the moon before proceeding to Earth, which is briefly seen in the series. The production art indicates the shots of the base were intended to be a great deal more extensive, but were presumably cut for time. AotSC, IIRC, even identifies a screen capture of that brief shot as a picture of Moon Base ALuCE. It's unknown if they had any kind of launch assistance from the lunar surface, but once in space the TLEAD-assisted Legioss had enough fuel to make a one-way trip to Earth orbit. The large warships were capable of interplanetary travel, but even then it was a trip of a couple weeks made possible by brute force nuclear fusion propulsion.

[ShadowLogan]

Logically, we would've expected there to be a ship somewhere just offscreen that ferried them into the area and recovered them to return to ALuCE base, given that the series depicts the Beta (and its capacious fuel tanks) as a necessary addition to the Alpha in order to make a one way trip from Luna to Earth... a much more forgiving course in terms of delta-v budget than going the other way. If the Alpha were capable of making the one-way trip in any reasonable timeframe, there wouldn't have been any reason for the UEEF to send so many Ikazuchi-class and Garfish-class ships to ferry them directly to Earth's orbit. Especially glaring given how vulnerable those ships are... and the operating profile we're told applied to both the UEDF/ASC and UEEF carriers. These aren't long-range, high-endurance space fighters meant for long-range cruises or patrols... they're short-ranged fighters meant to be launched from a carrier in close proximity to an enemy ship or planet. They didn't really need long-range cruise capability, because they had fold-capable ships to ferry them directly to the target.

If we go with the external support material to establish the Alpha's performance there are actually a few logical options all of which have issues IMHO:
1. "single transport of some kind" (Garfish, Ik, Horizon). BUT we know the available ship types can all land at ALUCE, why send the fighters ahead solo when you could just land the ship (ep84/85 does have all 3 NG ship types lifting from the facility). A shuttle could have been used to ferry Marucs & Alex down more effectively (and probably rotate other personnel down at the same time).
2. They used Betas for part of the transit, and left them in orbit (or they had them and omitted are treated as an AE OR evidence the UEEF has S.E.P technology -HHGTTG/LTUE ). The main problem here is there is no indication that the UEEF even uses the Beta in such a fashion. The closest we come is Sent OVA (AFAIK) on the test flight, but that was more of a field switch and a test flight. Marcus/Alex VF-6 cockpit displays DO show information on a connected Beta (IINM, but that could be an AE as they aren't seen)
3. Some type of orbital transfer catapult is available (this could take a few forms, but doesn't address how they slow down), but nothing like this is even hinted at being in use/around, so seems highly unlikely.
4. The Shadow Device itself can be used as a form of propulsion on its own or a "propulsion enhancer", which can be inferred from dialogue (TSC/series) and AotSC. But this means the (non-Super) Shadow Alpha should be in theory more agile than a regular unit, something I don't think we see, not to mention still remove the "short-legs in space".

Re: Need for ships still
I don't think it negates the need for the ships for several reasons:
1. Re-supply. Theoretically all of those ship types can refuel and 2/3 can rearm the Alpha. This requires recovery and relaunch. Maintenance could also be performed if something should break during the transit or in battle
2. Big Guns. Both the Garfish and Ikazuchi bring to the table BFGs that the Alpha can't match, granted those weapons are shown to have little actual impact against the Invid
3. Command & Control. This allows individuals to direct the battle in real time with minimal communication delay (~3sec round trip between Earth-Moon might not seem like much, but it could be a factor). Plus I would think that managing a large force and being an active participant would be very difficult (requiring someone who isn't a actively pilot/dogfighting)
4. Those bigger ships might be able to travel the distance FASTER than the Alpha (which means the Invid would have less time to respond), which they should be capable of doing. You probably also open up more options in terms of when you can launch, what approaches you can use, etc. Lets not forget that 10th and 21st MD arrived via Fold not staging from ALUCE (so non-Earth locations probably have to rely on ships to get there).
5. The use of ships also allows the pilots to arrive "fresh" as compared to those who would have taken the flight inside their cockpits (I would also think that launching all those VFs would take some time, so some pilots are going to be more "worn out" than others if its just a mass formation of VFs)
6. The ships are also supposed to be carrying ground troops and their equipment aren't they? You can't really do that with an Alpha (or even Beta) practically
7. Access to a closer battlefield hospital should one become injured (granted visually this doesn't happen for UEEF VFs, but it could theoretically given Rook/Rand/Scott's injury in their Alpha cockpit in the series, even Wolfe might have had survivable injuries with proper medical help)

If these aren't compelling reasons the UEEF could have simply devoted the resources from ship building to building more Betas to augment every Alpha, even IF we ignore TSC (which sounds like a better idea every day).

Short legs in space is a relative term.

Yes it is, but we have some indication of how "short" those legs are given that it can't reach orbit from Earth's surface w/o assistance. That means that the total Delta-V (range determiner) available to the Alpha MUST fall under a fixed threshold (IIRC ~8kps, more if we consider velocity loss due to atmospheric drag and gravity on the trajectory or even specific orbital inclinations it will be a bit more).

Remember the OSM had the Horizontal etc attacking from Mars. The Alpha's short range may be that it can't make this trip on its own (hence the carrier craft). Getting from Earth to the Moon is a very small fraction of this distance.

In terms of physical distance there is that, but from a Delta-V standpoint the difference between an Earth-Mars or Earth-Moon flight is much smaller, at least from a minimum requirement POV IIRC. However the longer the Legois has to transfer from Mars to Earth means it has to carry that much more in terms of consumables, space/mass that would have to come from somewhere (trade-off or make the unit larger). Then there are others that would need to be addressed in terms of life support (radiation protection, muscle atrophy, etc). All of which adds up to making the "capital ships" making more sense for the journey than attempting to do it with a fightercraft.

[Seto Kaiba]

If we go with the external support material to establish the Alpha's performance there are actually a few logical options all of which have issues IMHO:
1. "single transport of some kind" (Garfish, Ik, Horizon). BUT we know the available ship types can all land at ALUCE, why send the fighters ahead solo when you could just land the ship (ep84/85 does have all 3 NG ship types lifting from the facility). A shuttle could have been used to ferry Marucs & Alex down more effectively (and probably rotate other personnel down at the same time).

Presumably they would want to keep the reconnaissance operation as unobtrusive as possible, given that they would already have had reason to suspect that the Invid could still see a ship with a shadow field stealth system using regular optical sensors... but sending Shadow Fighters at all doesn't make sense, as they're not reconnaissance craft and not outfitted with any special detection systems. A shadow field-stealthed Garfish-class with the sensor pod would've made more sense...

2. They used Betas for part of the transit, and left them in orbit (or they had them and omitted are treated as an AE OR evidence the UEEF has S.E.P technology -HHGTTG/LTUE ). The main problem here is there is no indication that the UEEF even uses the Beta in such a fashion. The closest we come is Sent OVA (AFAIK) on the test flight, but that was more of a field switch and a test flight. Marcus/Alex VF-6 cockpit displays DO show information on a connected Beta (IINM, but that could be an AE as they aren't seen)

I think we can rule out a Someone Else's Problem field... after all, they didn't paint the fighters pink first. Bistromatic drives and Infinite Improbability systems are probably out too as none of the UEEF staff seem the tea drinking type, and the fine link to the unreality that is the waiter's check pad has probably been lost in their purely military lifestyle.

Using Betas for the transit is one of the more likely explanations, though the Betas displayed on the MFD in the cockpit during that sequence is a clear animation error since it shows them docked when no Betas are actually docked at that time.

4. The Shadow Device itself can be used as a form of propulsion on its own or a "propulsion enhancer", which can be inferred from dialogue (TSC/series) and AotSC. But this means the (non-Super) Shadow Alpha should be in theory more agile than a regular unit, something I don't think we see, not to mention still remove the "short-legs in space".

Seems unlikely... in the series they don't mention any kind of performance enhancement in connection with the shadow stealth feature. The way it's described isn't even consistent between those two versions, given that in the series the description makes the stealth out to be passive stealth as a result of design changes to the fighter's power plant, whereas in the OVA it's active stealth by way of an ersatz cloaking device.

The OVA and Prelude do indicate that shadow fields can be used for gravitational field damping, though the only occasion on which we see one used to escape a gravity well made it a fold system the active agent and the shadow field merely helped the fold bubble form properly. It would have been an interesting potential explanation... instead of anti-grav, a form of gravity-exemption for shadow stealthed craft that would permit them to ignore gravity wells. Kind of an inverse version of the Inertia Store Converter from Macross. 'course it would still be problematic, given that Marcus and Alex's shadow fighters are shown to have shadow fields turned off during the Wolf Recon scene. It would've had interesting implications for ships too...

If these aren't compelling reasons the UEEF could have simply devoted the resources from ship building to building more Betas to augment every Alpha, even IF we ignore TSC (which sounds like a better idea every day).

Hey! That was a brilliant idea back in August of '06, and it stood the test of time... and the whims of the Robotech.com moderators.

Short legs in space is a relative term.

Yes it is, but we have some indication of how "short" those legs are given that it can't reach orbit from Earth's surface w/o assistance. That means that the total Delta-V (range determiner) available to the Alpha MUST fall under a fixed threshold (IIRC ~8kps, more if we consider velocity loss due to atmospheric drag and gravity on the trajectory or even specific orbital inclinations it will be a bit more).

Probably less, given that the Alpha/Shadow fighter isn't using propellant fro the onboard tanks for the entire ascent either... for a good chunk of that it's using intake air instead, so the propellant limitations are probably significantly less than that ~9kps they'd need to launch to orbit from the surface and it STILL can't get there.

[ShadowLogan]

Presumably they would want to keep the reconnaissance operation as unobtrusive as possible, given that they would already have had reason to suspect that the Invid could still see a ship with a shadow field stealth system using regular optical sensors... but sending Shadow Fighters at all doesn't make sense, as they're not reconnaissance craft and not outfitted with any special detection systems. A shadow field-stealthed Garfish-class with the sensor pod would've made more sense...

I meant solo from the Garfish back to the Lunar Surface, I have the same question about sending Shadow Fighters on a Recon flight myself. The Best ship (IMHO) to use for a recon flight I would think would be a Horizon as opposed to a Garfish.

Using Betas for the transit is one of the more likely explanations, though the Betas displayed on the MFD in the cockpit during that sequence is a clear animation error since it shows them docked when no Betas are actually docked at that time.

I agree it's an AE, at least from memory. I don't recall how much it differs from when a Beta is actually depicted later, or if there's a difference (I'm not saying there is or not, I don't recall/notice) it could just be part of the revised cockpit to have a dedicated display for the Beta (Why, I don't know since the vast majority of Shadow Alphas don't get a Beta)

Seems unlikely... in the series they don't mention any kind of performance enhancement in connection with the shadow stealth feature. The way it's described isn't even consistent between those two versions, given that in the series the description makes the stealth out to be passive stealth as a result of design changes to the fighter's power plant, whereas in the OVA it's active stealth by way of an ersatz cloaking device.

The OVA and Prelude do indicate that shadow fields can be used for gravitational field damping, though the only occasion on which we see one used to escape a gravity well made it a fold system the active agent and the shadow field merely helped the fold bubble form properly. It would have been an interesting potential explanation... instead of anti-grav, a form of gravity-exemption for shadow stealthed craft that would permit them to ignore gravity wells. Kind of an inverse version of the Inertia Store Converter from Macross. 'course it would still be problematic, given that Marcus and Alex's shadow fighters are shown to have shadow fields turned off during the Wolf Recon scene. It would've had interesting implications for ships too...

I agree it seems unlikely, and the Recon Flight had the field turned off (they could have turned it back on for the flight), but then again if we compare TSC to Ep84-5 none of the Shadow equipped hardware show that visible field so it might not amount to much (since series trumps later works).

AotSC pg40 casts them as having a common property to Fold Drives, the Masters also use a form of space folding in their Bio-Magnetic-Induction-Network ("Danger Zone"). I was thinking something along those lines where it manipulates gravity fields to warp/fold space providing motion (ala the BMI). The only other way would be to use the system to somehow mask the craft's own mass (or part of it) from itself so that the propulsion system thinks its pushing something lighter than ~17tons.

Probably less, given that the Alpha/Shadow fighter isn't using propellant fro the onboard tanks for the entire ascent either... for a good chunk of that it's using intake air instead, so the propellant limitations are probably significantly less than that ~9kps they'd need to launch to orbit from the surface and it STILL can't get there.

If we assume that the specs on the Alpha family have the max speed of 3000kph at 30km altitude is the limit of airbreathing mode (alt and speed), they could save ~ 0.8kps in Delta-V if they can use that velocity as a spring board (depending on desired trajectory and launch location they could even get an extra free boost from the Earth). So they would still need about 8kps to reach orbit, which we are told it can't do, so it still puts an upper edge limit. Yes if the airbreathing mode can continue to operate at a higher altitude (and speed) it would help.

The series does at least help establish a lower limit, IF we assume the Alpha achieved orbital velocity on its own at the Moon (in Sue's footage, Ep83) it would need ~1.6kps (2.4kps if it escapes Lunar gravity) more if we assume you want a safe landing (x2, since you can't use air to slow you down completely) and want some margin for combat/flyaround and need to overcome gravity reductions to velocity. There are other factors that would push it even higher, just using the Moon footage, but that gets into more assumptions about the orbital parameters than I feel comfortable with at this point. For comparison the Apollo Lunar Module had a combined Delta-V of ~4.6kps between it's two modules that handled both ascent (2.4) and decent (2.2). So putting a lower estimate on the Alpha at ~5kps seems reasonable.