A question of VF Aero Dynamics

[Wanzerfan]

The old VF Valkyries are based off of the old F-14s, the wings sweep when needed (although why the wings need to be deployed fully in space is beyond me; could be the thing has OMS in the wings).

When the Valk changes to Battloid (I do believe that is the most accurate translation) the vertical stabalators fold inward and down, and the aft fuselage folds ventral and fore 180 degrees as the legs lower and the arms deploy and the gunpod detaches from the belly and is grabbed by the right hand of the craft as this happens to form the GERWALK configuration. The wings then sweep back all the way and lock into each other to form the lower back. The fore and aft sections of the ventral fuselage split, while the legs break away and reattach on either side of the nose of the craft, and the fighter folds in half to form the torso. The belly turrent is deployed as the head of the battloid . The torso locks together completing the transformation.

Edited May 11, 2009 by Wanzerfan

[Gubaba]

The old VF Valkyries are based off of the old F-14s, the wings sweep when needed (although why the wings need to be deployed fully in space is beyond me; could be the thing has OMS in the wings).

When the Valk changes to Battloid (I do believe that is the most accurate translation) the vertical stabalators fold inward and down, and the aft fuselage folds ventral and fore 180 degrees as the legs lower and the arms deploy and the gunpod detaches from the belly and is grabbed by the right hand of the craft as this happens to form the GERWALK configuration. The wings then sweep back all the way and lock into each other to form the lower back. The fore and aft sections of the ventral fuselage split, while the legs break away and reattach on either side of the nose of the craft, and the fighter folds in half to form the torso. The belly turrent is deployed as the head of the battloid . The torso locks together completing the transformation.

Um, yeah...we know. We've all seen Macross. That's why we're here.

And it's generally "Battroid," not "Battloid."

[Rbstr]

GAh! Turret, not turrent.

Where the hell does the word "turrent" come from? So many people use it it it's so...not a word.

It can't be a typo because 'n' isn't anywhere near turret. It's on the bottom, all the rest of on the top row.

Edited May 11, 2009 by Rbstr

[Gubaba]

GAh! Turret, not turrent.

Where the hell does the word "turrent" come from? So many people use it it it's so...not a word.

It can't be a typo because 'n' isn't anywhere near turret. It's on the bottom, all the rest of on the top row.

I totally missed that...but now that you point it out, yeah, that's weird.

I guess it's like people typing "cannon" when they really mean "canon."

[mickyg]

thanks man!

what do you use for propulsion?

i was thinking that only a propeller

can be used to make a model plane fly?

maybe you can make one which

transforms to gerwalk when landing.

Ok, this is far too cool not to comment on - This thing is awesome! Talk about testing aerodynamics! The thread where IAD shows us how this was built is HERE.

IAD - if you haven't already put a thread up on this forum, you're missing out on some much needed feedback from this community. Your work is nothing short of amazing!

So anyway, maybe the SV-51 is more aerodynamic than a VF-1 but nonetheless, this proves that just because it's anime, it doesn't mean it can't fly.

[anime52k8]

I totally missed that...but now that you point it out, yeah, that's weird.

I guess it's like people typing "cannon" when they really mean "canon."

at least both cannon and canon are actual words and are pronounced the same way. turrent doesn't even read the same as turret.

'Turrent' is only one letter off from 'torrent' though, someone's been doing a lot of downloading lately maybe?

[geepogi]

Ok, this is far too cool not to comment on - This thing is awesome! Talk about testing aerodynamics! The thread where IAD shows us how this was built is HERE.

man! that is a 36 page thread!

awesome work man! didn't realise

it was scratch-built. i thought he

already had a ready made model

and he just slapped on the propulsion

system. awesome!

[David Hingtgen]

IAD's Sv-51 is so awesome, Shoji Kawamori has seen the footage of it flying, and it was briefly shown on TV in Japan as part of a Macross special.

[SchizophrenicMC]

IAD's SV-51 uses ducted fans, not props.

You can use Jet turbines, as well, to power R/C flight.

Moving on, no need to explain our beloved VF-1 to us, Wanzerfan. Also, stop using Battloid as the term for Battroid. People will get angry.

Turret - a rotary weapons mount

Turrent - made-up portmanteau of Turret and Torrent

Cannon - a weapon

Canon - relating to a story, but not necessarily explained in the story's original content

[Beltane70]

at least both cannon and canon are actual words and are pronounced the same way. turrent doesn't even read the same as turret.

'Turrent' is only one letter off from 'torrent' though, someone's been doing a lot of downloading lately maybe?

Turrent is nothing recent. I have a friend that has been using the word turrent instead of turret for the twenty years that I've known him! He used to GM our role-playing games and pretty much every time he used turrent, I'd turn to one of my other friends and ask, "what the hell's a turrent?". We found it so funny that we never actually bothered to correct him.

[IAD]

...IAD - if you haven't already put a thread up on this forum, you're missing out on some much needed feedback from this community. Your work is nothing short of amazing!

There is a thread here, under Fan Works...

http://www.macrossworld.com/mwf/index.php?showtopic=15665

It's quite long, but pretty comprehensive.

Regarding the VF-1... I've posted this list before, but in my opinion, the following VFs could be made to fly very well as RC ships, while keeping true-to-lineart outlines:

VF-0A/D/S (-0D would be easiest), VF-1, VF-4, VF-11, YF-19/VF-19 (did some work on this, it flew, but it was just a pusher-prop job), YF-21/VF-22 (want to do the latter), VF-17/171, VF-25, VF-27.... Pretty much everything except the Plus Ghost? (And even that could be done, given great attention to weight, and gross excess of thrust.)

Kawamori's designs are pretty reasonable, when it comes to making them fly as models... They have lots of (unnecessary) drag, but they do have enough stabilizer/wing area (in the right places), decent-sized intakes/exhausts, and enough control surfaces to make them work in the end. (Which is more than can be said for the FRX-99 Yukikaze... Which I still want to build/fly one day.)

~Luke

Edited May 13, 2009 by IAD

[mickyg]

There is a thread here, under Fan Works...

http://www.macrossworld.com/mwf/index.php?showtopic=15665

It's quite long, but pretty comprehensive.

Regarding the VF-1... I've posted this list before, but in my opinion, the following VFs could be made to fly very well as RC ships, while keeping true-to-lineart outlines:

VF-0A/D/S (-0D would be easiest), VF-1, VF-4, VF-11, YF-19/VF-19 (did some work on this, it flew, but it was just a pusher-prop job), YF-21/VF-22 (want to do the latter), VF-17/171, VF-25, VF-27.... Pretty much everything except the Plus Ghost? (And even that could be done, given great attention to weight, and gross excess of thrust.)

Kawamori's designs are pretty reasonable, when it comes to making them fly as models... They have lots of (unnecessary) drag, but they do have enough stabilizer/wing area (in the right places), decent-sized intakes/exhausts, and enough control surfaces to make them work in the end. (Which is more than can be said for the FRX-99 Yukikaze... Which I still want to build/fly one day.)

~Luke

I read all 36 pages on the RC forum after posting that comment - apologies for assuming it hadn't been put here. I sometimes forget I'm a relatively new MWer and there's a lot I haven't read yet!

Good to know about the other models that would fly. I've often looked at my Yamato VF-1 and thought about what would be necessary to get it to fly. Not the toy, but something modelled off of it. In my opinion, there are too many holes and gaps in it to make it aerodynamic. Still, it looks doable.

Again, thanks for posting your stuff. You're doing things that a lot of us will only ever imagine or at best, read about. Heck, I didn't even know about EDF motors until two days ago when I read your build thread. But that's WAY off topic!

[SchizophrenicMC]

There is a thread here, under Fan Works...

http://www.macrossworld.com/mwf/index.php?showtopic=15665

It's quite long, but pretty comprehensive.

Regarding the VF-1... I've posted this list before, but in my opinion, the following VFs could be made to fly very well as RC ships, while keeping true-to-lineart outlines:

VF-0A/D/S (-0D would be easiest), VF-1, VF-4, VF-11, YF-19/VF-19 (did some work on this, it flew, but it was just a pusher-prop job), YF-21/VF-22 (want to do the latter), VF-17/171, VF-25, VF-27.... Pretty much everything except the Plus Ghost? (And even that could be done, given great attention to weight, and gross excess of thrust.)

Kawamori's designs are pretty reasonable, when it comes to making them fly as models... They have lots of (unnecessary) drag, but they do have enough stabilizer/wing area (in the right places), decent-sized intakes/exhausts, and enough control surfaces to make them work in the end. (Which is more than can be said for the FRX-99 Yukikaze... Which I still want to build/fly one day.)

~Luke

Ah, the Yukikaze... I would LOVE to see a real plane do that move where it flips DOWN, pulls out just over the ocean, and flies at the enemy ship.

[anime52k8]

Ah, the Yukikaze... I would LOVE to see a real plane do that move where it flips DOWN, pulls out just over the ocean, and flies at the enemy ship.

Don't forget the part where the wings rotate 180 degrees while executing the flip. oh, and then when they roll backwards off the deck of the carrier, hover at deck level using only engine thrust, then clime vertically at high speed.

I would love to see a VF-4 RC model.

[SchizophrenicMC]

Don't forget the part where the wings rotate 180 degrees while executing the flip. oh, and then when they roll backwards off the deck of the carrier, hover at deck level using only engine thrust, then clime vertically at high speed.

I would love to see a VF-4 RC model.

Yup...

I have the Super Silph in FSX, and it only flies because the model doesn't control the flight data.

Its CFG file's got the same attributes, almost, as the FS8 VF-1's

[IAD]

Yep, that's just it, while none of the VFs are particularly efficient, they nevertheless can still be made to fly reasonably well. (At a small [light] scale, anyway.)

The flip is definitely a 'must-do' maneuver... Fortunately, the rotating wings aren't technically required to pull it off. Enough mass, enough thrust, and enough thrust-vector travel should do the job just fine. The carrier launch is more challenging, since the thrust/weight ratios required for the fast vertical climb are hard to achieve in a 'jet' model... (Turbines might work, or just hide a couple pusher propellers on it somewhere.) Hovering isn't too bad, even with turbines:

(2:20, but the whole thing is worth a watch.)

The Silphs are fine planes, in terms of aerodynamics... A little short-coupled, and a lot of side area ahead of the CG, but generous intake area, which is good for EDFs.

~Luke

Edited May 13, 2009 by IAD

[SchizophrenicMC]

Yep, that's just it, while none of the VFs are particularly efficient, they nevertheless can still be made to fly reasonably well. (At a small [light] scale, anyway.)

The flip is definitely a 'must-do' maneuver... Fortunately, the rotating wings aren't technically required to pull it off. Enough mass, enough thrust, and enough thrust-vector travel should do the job just fine. The carrier launch is more challenging, since the thrust/weight ratios required for the fast vertical climb are hard to achieve in a 'jet' model... (Turbines might work, or just hide a couple pusher propellers on it somewhere.) Hovering isn't too bad, even with turbines:

(2:20, but the whole thing is worth a watch.)

The Silphs are fine planes, in terms of aerodynamics... A little short-coupled, and a lot of side area ahead of the CG, but generous intake area, which is good for EDFs.

~Luke

Seen that...

Anyway, the Super Silph does NOT a flip perform. A flip is when you pull the nose up hard. It pushes down harder than most planes can pull up; something that is impossible, anyway, due to aerodynamics.

[anime52k8]

Seen that...

Anyway, the Super Silph does NOT a flip perform. A flip is when you pull the nose up hard. It pushes down harder than most planes can pull up; something that is impossible, anyway, due to aerodynamics.

if you just ignore how impossible what you're seeing is, Yukikaze is one of the Best OVA's ever visually.

[SchizophrenicMC]

if you just ignore how impossible what you're seeing is, Yukikaze is one of the Best OVA's ever visually.

I will agree on that note, but it's against my morals to ignore it...

It is not a super robot anime, thus I cannot see it as such.

[IAD]

From a 'real physics' standpoint, the diving inverted flip is NOT impossible, assuming the pilots don't red out... The maneuver is certainly no more 'super robot' than the whole concept of a transforming fighter jet.

As I see it, you'd push the nose over, hold the dive for a second to build speed, and then bury the stick in the upper stop. With enough thrust-vector power, you'd stall the wings out while still diving (angle of attack is with reference to velocity vector, not horizon), but the momentum would continue to carry you downwards, countered only by the drag generated by the now-stalled wings.

Continue holding the forwards stick, and the thrust vector will pivot the aircraft around its center of mass. As the nose passes vertical, the engine thrust should help decrease the descent rate, and as a result, the effective angle of attack. Timed precisely, your wings would start generating lift again just as you came to about 10 deg. nose up, at which point, you let off the forwards stick, and fly out.

Unfortunately, on a small model, the ratio of inertial/aerodynamic forces is low, so the drag of the stalled wings would tend to overcome the downward momentum very easily, preventing the aircraft from falling uniformly while pitching the nose around... So, obviously, a big model would be needed!

~Luke

Edited May 14, 2009 by IAD

[SchizophrenicMC]

Snippet

Fall, I can see happening. I can even see the recovery.

However, the start-out doesn't quite work. Lift and air resistance prevent it from snapping so quickly downwards. Planes can do so upwards, because lift on the body pulls them up. You'll notice while flying a high-performance plane (R/C is a pretty bad judge for the real, due to proportion issues between volume and weight) that you pull up faster than down, even in FBW.

[IAD]

I disagree, aerodynamically, for roughly symmetrical body (in the aerodynamic sense of the word, wings, fuselage, etc.), "lift" is arbitrarily said to be "up"... "Lifting" down is just as easy as lifting up... Easier, in fact, since you get a 9.81 m/s^2 downward boost.

As for whether the Yukikaze should be considered a roughly symmetrical body... With the number full-flying control surfaces (canards, wings, tails) I'd say it's close enough. Even if all the surfaces were simple flat plates, the "lift" generated would be more than enough to achieve the pitch rates needed.

Now, what is true is that pilots red out a lot easier than they black out... Thus, in real life, nobody ever snaps their nose down as fast as they do pulling up. By extension, airframes are designed with much lower negative G tolerance, since the pilot is the weak link there anyway... (One more incentive never to pitch down that fast.)

What you say is particularly true for fly-by-wire, since the computers ensure the pilot can't overstress the airframe.

As for RC/real life... Definitely, that's why nobody's done a real cobra with a model Su-37, etc... However, it's also true that the Yukikaze is a horrible design in real life, so I have little interest in whether a "real" version could perform a given maneuver... But whether a model could be made to is definitely a point of interest.

~Luke

[SchizophrenicMC]

I disagree, aerodynamically, for roughly symmetrical body (in the aerodynamic sense of the word, wings, fuselage, etc.), "lift" is arbitrarily said to be "up"... "Lifting" down is just as easy as lifting up... Easier, in fact, since you get a 9.81 m/s^2 downward boost.

As for whether the Yukikaze should be considered a roughly symmetrical body... With the number full-flying control surfaces (canards, wings, tails) I'd say it's close enough. Even if all the surfaces were simple flat plates, the "lift" generated would be more than enough to achieve the pitch rates needed.

Now, what is true is that pilots red out a lot easier than they black out... Thus, in real life, nobody ever snaps their nose down as fast as they do pulling up. By extension, airframes are designed with much lower negative G tolerance, since the pilot is the weak link there anyway... (One more incentive never to pitch down that fast.)

What you say is particularly true for fly-by-wire, since the computers ensure the pilot can't overstress the airframe.

As for RC/real life... Definitely, that's why nobody's done a real cobra with a model Su-37, etc... However, it's also true that the Yukikaze is a horrible design in real life, so I have little interest in whether a "real" version could perform a given maneuver... But whether a model could be made to is definitely a point of interest.

~Luke

Cobra's only because their thrust-to-weight is too high. The planes don't like to snap up like that, remain moving in the same direction, and not deflect upwards.

And I say FBW, because those planes are designed unstable, so that they can perform sharper maneuvers, and can only really fly because the flight computer constantly adjusts their control surfaces.

Moving back on topic from the Yukikaze,

The bigass fin on the bottom. Why?

And this goes also for the RVF-25.

[m0n5t3r]

Ok, this is far too cool not to comment on - This thing is awesome! Talk about testing aerodynamics! The thread where IAD shows us how this was built is HERE.

IAD - if you haven't already put a thread up on this forum, you're missing out on some much needed feedback from this community. Your work is nothing short of amazing!

So anyway, maybe the SV-51 is more aerodynamic than a VF-1 but nonetheless, this proves that just because it's anime, it doesn't mean it can't fly.

wow! that RC SV-51 by IAD is all kinds of awesome!

[IAD]

"Cobra's only because their thrust-to-weight is too high..."

Sacrilage! There is NO such thing as too much thrust!

The big fin is an ELINT antenna, isn't it?

Both the Slyph and the RVF-25 were electronic warfare/intelligence aircraft, after all.

~Luke

[SchizophrenicMC]

"Cobra's only because their thrust-to-weight is too high..."

Sacrilage! There is NO such thing as too much thrust!

The big fin is an ELINT antenna, isn't it?

Both the Slyph and the RVF-25 were electronic warfare/intelligence aircraft, after all.

~Luke

It's understandable on the RVF, since ELINT is, supposedly, a made-up Macross term, and it's a space fighter, but on the Sylph, notsomuch. I mean, for the benefits it adds, it generates rolling drag, which can rip it off in a high-g roll. That's not good, for obvious reasons. And, ELINT could be performed by a smaller sensor, right? I mean, the VE-1 did it without a bigass fin.

[Pat S]

If you really want to rip on something, Macross Plus had some major anime magic where Isamu was entering earth's atmosphere and the YF-19 started to tumble with no power (to keep from getting sighted by UN Spacy weapons). I think the ship would have burnt up immediately, and Isamu would have blacked out right then and there.

They're sci-fi cartoons, give them some slack. I'm impressed that the radio control renditions fly at all.

[IAD]

ELINT is NOT a Macross-only term... It's Electromagnetic Intelligence, and a very real field.

The Slyph was an ELINT aircraft... In the first episode, the downward facing fin (antenna) was stowed immediately after they completed monitoring the battle. When they chased the phantom Slyph, the antenna was retracted. You could argue landing gear are also liability... Extended at the wrong time, they can rip off, add a lot of drag, etc... But that's why you retract them.

Though taken to the extreme in these cases, you can't just take an antenna and make it smaller, without losing specific characteristics... The required size is dependent on a number of factors, but... After all, there is a reason that AWACs have huge radomes, and (real-life) ELINTs have their antenna farms.

http://www.defenseindustrydaily.com/images...uardrail_lg.jpg

(And also why cell towers are towers, and not little black boxes hidden away out of sight, which would definitely be nicer.)

The VE-1 had a radome... (Now, technically, that makes it more of an AWAC....)

~Luke

[SchizophrenicMC]

If you really want to rip on something, Macross Plus had some major anime magic where Isamu was entering earth's atmosphere and the YF-19 started to tumble with no power (to keep from getting sighted by UN Spacy weapons). I think the ship would have burnt up immediately, and Isamu would have blacked out right then and there.

They're sci-fi cartoons, give them some slack. I'm impressed that the radio control renditions fly at all.

Well, realize this also: The ECA is still active as long as the tubines are producing power. Further, it's made of "space metal" which seems to have the capability to withstand that heat.

Further, Isamu's an ace pilot of a variable fighter and has acclimated himself to high g-loads. He was hiccing the whole time and straining to remain concious. Thus, it shows how even the most storied pilots struggle against that.

You've gotta remember that Shoji Kawamori, unlike many other mecha designers, likes to base his designs off of real physics. You see the VF-1? It's known to be able to fly, as is its cousin, the VF-0; the SV-51, and the VF-11. They're least off the beaten path. Of course, the VF-25 can, too, and the VF-27 probably can, since it's similar to the SV. Then, there are the more exotic designs, like the -19, -17, and-22. The 22 can fly, of course, since it really follows even the conventional laws, and the 17's extremely simliar to the F-117. The VF-19, however, is quite different. It has forward-swept wings. Now, we know that flies. Further, its wings swing backwards.

The physics behind them explain how they can possibly fly.

The VE-1 had a radome... (Now, technically, that makes it more of an AWAC....)

~Luke

Yeah, but VE is stated to mean Variable ELINT, more specific than Variable Electronic.

[badboy00z]

What are the advantages and disadvantages of having the vertical fins set at an angle as suppose to 90 degrees?

[SchizophrenicMC]

What are the advantages and disadvantages of having the vertical fins set at an angle as suppose to 90 degrees?

It means you don't have to worry as much about rolling drag as with 90s, for one. (See ELINT Fin issue)

A few more issues with that, I'm not too familiar with, so I'll let someone else do it.

[anime52k8]

It means you don't have to worry as much about rolling drag as with 90s, for one. (See ELINT Fin issue)

A few more issues with that, I'm not too familiar with, so I'll let someone else do it.

they probably do it for the same reason they angle the wings and fins. reduce drag and increase stability at higher speeds.

[SchizophrenicMC]

they probably do it for the same reason they angle the wings and fins. reduce drag and increase stability at higher speeds.

See, that's what I was thinking.

Dex, please answer us! You're at ERAU-Az!

[David Hingtgen]

Angled tailfins are mainly for retaining control/stability at high-alpha-----a vertical fin will be operating in the wake of the fuselage at high-alpha, while ones canted outwards will get clean air.

[anime52k8]

Angled tailfins are mainly for retaining control/stability at high-alpha-----a vertical fin will be operating in the wake of the fuselage at high-alpha, while ones canted outwards will get clean air.

oh... OH I see what you mean now. for some reason I thought we were talking about why the ELINT fin was swept back... durrr.

anyways, what he said plus out canted tail fins help reduce RCS.