Project Here goes nothing: The Delta-StarLiner G42

[Moach]

what day is it? - that's right! IT'S TUESDAY!!

and did i not say we would have a new WIP tonight? - well here it is!
this one is a bit bulky because i decided to include all my sources (which is proving to be a 71mb mistake)... but i'ts good, because now i have a safe backup in case of zombie attacks or similar inconvenient events... 11% uploaded, anyways...


as for new features, now a first draft of the engine procedures is being simulated - complete with sounds, up to the last stage, which has none yet...

the engines now respond differently from the stock DG - specially the mains, which are turbine-hybrid rockets, have a noticeble delay between throttle and thrust :thumbup:


20% uploaded....


the lastest addition are the animated control surfaces - now you can see how the "flight computer" filters stick input into the combined-axis surfaces... this would be an engineering nightmare without the advent of fly-by-wire

speaking of which - the ship is now MUCH easier to fly... it should handle like a heavier, yaw-happy DG - but now it's flyable by human hands without it being the last thing a pilot would do in his life...


30% of upload.... man, that thing is large....


the DARTS, death-traps they are, should be only needed for super-heavy payloads, as the fuel supply is very tight.... but let's leave those for last... we still need to be able to actually lift cargo before we start strapping doom-in-a-can to the ship, right? :lol:


40%.... weh...


included in this pack, is also the dxstudio file i'm using to convert the image maps into arrays for use in the engines flight envelope simulation... if you wanna use it, it'll have to install the DXStudio player first... it's free, like a Flash Player, of sorts, but more awesome...

anyways, in a few more steps, it won't be needed anymore - i've come by a most convenient BMP handling library, and i'll have my code re-done so it reads directly from the BMP files, instead of that whole copy-paste shanennigans i have going on here :shifty:


52%... c'mon! i wanna go to sleep!....


crap, i accidentaly closed it :uhh:



ah! man.... it's gonna have to start all over again....

i think i'll leave it uploading and retire for today... WIP-02 will be available shorly


http://code.google.com/p/dga2/downloads/list <---- link



edit:

it's uploading again - i managed to get most of the bulk out of the file by removing a redundant SFX folder and some other useless things.... should be up in a bit

 

[River Crab]

:woohoo:
WOOHOO!
EDIT: oh yeah. :/


:woohoo:
WOOHOO Again!
I got it!
:hail:
Also, who downloaded it before me!

 

[Moach]

Am I reading this wrong? 49 downloads in 4 MINUTES!?
WOOHOO!

uh... probably not... it's not done uploading yet - the one in there is the old version, which i think you already have


we're at 70% upload now

 

[Izack]

Funny, it's been Tuesday here (what is this Wednesday thing?!) for only 50 minutes (40 at the announcement post) and it's already awesome. Also, it's my day off so Starliners away all day! :hail:

I should be at the controls by 0120.

 

[Moach]

just a quick note - upload is complete!

get it here: http://code.google.com/p/dga2/downloads/list
(yep, same link as above)

 

[Jamesep3]

I downloaded it and it said it had been uploaded 3 mins ago. The local time is 3:58pm WEDNESDAY. so much for the release on Tuesday. I know not your fault time zones is whats caused the problem right.:lol:

 

[River Crab]

Aug 3rd, 2010, 23:53

IS A MIRACLE! :hail:
Just so everyone knows, the world runs on US eastern time 'cause that's where the big ball drops.

Back to flying, full orbital flight this time! No sleep till daylight! Let that fox lady wake me up at dusk, 'cos it's Killing Time! (Try flying to this song, just try it)

 

[Usquanigo]

Let that fox lady wake me up at dusk, 'cos it's Killing Time! (Try flying to this song, just try it)

Not bad. :headbang:

Very reminiscent of Stradivarius.


When I see that title though I can't help but think of this -

:headbang::headbang:


Look forward to trying this plane tomorrow.

 

[Moach]

omg, that was the headbangest thing i've ever seen!

 

[Izack]

:headbang::headbang::headbang::headbang:

Alright, that aside...I've noticed some crazy control problems. The inability to stop banking (the thing just keeps slowly rolling) is still there, and now I've noticed that as I get higher up, it starts inexplicably yawing and rolling to the right.

 

[Moach]

to the right? strange... mine pulls a bit to the left :huh: (it really does)


i have no idea why it does that... i figured it was stable enough, but maybe i've grown accustomed to it... having an x52pro also makes everything seem easier and more controlled, as it is considerably more precise than the average joystick... so what might seem steady to me could feel OMG-out-of-control-we're-gonna-diiiiiieeeeee!!! to someone else :uhh:


still have some more flight tuning to do... having some brave test pilots really helps now :thumbup:


the no-airbrakes thing as also a regular death trap... i'm not sure i ever managed to get her down properly without engine assist.... back when i flew sailplanes in RL, they all had airbrakes - maybe you need either engines or brakes for a safe landing to be possible :hmm:

 

[Usquanigo]

Not to be a drag... but a design like that really should be instable about the yaw axis at high transonic speeds.

For some reason, yaw stability decreases when you get moving over Mach 2. This is one of the reasons the XB-70 had it's outer wings fold down. Yes, it was done primarily to contain the shockwave and get more lift with less drag, however, it had the added benefit of simultaneously increasing vertical surface area and increasing yaw stability, without the need for larger (permenant) vertical tail surfaces (which would have meant more weight and more drag at all flight regimes).

If you look at the Space Shuttle, it has a gigantic v-stab too. On normal planes, if you have twin engines, you want a larger v-stab in case you have an a-symmetrical thrust situation, or, you need to use twin tails, either-or. However, the Shuttle is unpowered, yet it still has that disproportionately large v-stab.

In fact, even WWII pilots complained about moving from razor backs to bubble tops, even that loss of vertical surface area led to reduced yaw stability. And they were positively crawling by comparison.

 

[Moach]

yes, for those very reasons, the G42 is known to have some funky yaw behaviour..... it IS, above all, a plane without any rudders... which is by its own nature a highly unstable design....


if it wasn't for fly-by-wire guidance systems, she would be as controllable as a frisbee most of the way


remember, this is NOT the Delta-Glider... this ship, even with FBW is know to be tricky to fly - and even so, i'm still tuning her for more comfort, but i'm not gonna make so that it flies as forgivingly as does the DG....

it's a delta-wing with no rudders, for crying out loud - that's the most insane combination in terms of stability :rofl:


she's bound to crab a little bit.... it's not a bug, it's a feature!:thumbup:

 

[Usquanigo]

she's bound to crab a little bit.... it's not a bug, it's a feature!:thumbup:

:thumbup:

I was posting in the hope of not seeing it overly tamed (I have to admit, I haven't had time to even get it up, just referring to Izacks post and your reply to him).

I still have my doubts as to an SSTO even being possible in the first place (though I really hope that it is - without some unforseen breakthrough in either propulsion or fuel storage (like metallic H2 or something)), so best to add in as much difficulty as possible IMO.

I had thought about pointing out that there are no supersonic flying wings, but that's not really a flying wing. The reason for that is that the center of pressure (lift) moves aft as you go past the mach, and without BOTH the lever arm of a normal tail, and the authority of an all flying tail, you'll get uncontrollable mach tuck and lawn dart. (like the soviet Bi-1 pilots discovered lol)

But since you went with a delta, you have the leverage to handle it. And we know that deltas are supersonic capable anyway (space shuttle, mirage, euro-fighter, F-16 XL, etc).

That leaves only yaw stability as an issue. And it ought to be a big one. lol (well, that and IMO it ought to be hard pressed to just barely make it to orbit even with only the bare minimum crew on-board, passengers or cargo (which should itself be minimal at best) ought to require help)

 

[Moach]

the G42 concept covers the facct that it does not use H2 as propellant...

the main reasons being that such fuel is tremendously bulky, and requires heavy insulation since it can only be stored in cryogenic temperatures.... not to mention it's a nightmare to make sure there are no leaks, since the damn thing is so thin....

no, too much headache... we're going the russian way - dense fuels!

i initially had thought of something like J-8... but as a futuristic craft, we don't want none of those petrol-based stuff... so we're using bio-fuels, which burn harder and cleaner (and most importantly, oodles cheaper)...
Brazil does have a lead on such technology (we've been driving on alcohol since before i was born) - and nowadays, most new car models here have "flex" engines, which can run on any mix of alcohol and gasoline... tho i have yet to get myself one of those , alcohol is sooo much cheaper



as you mentioned, it IS hard to get her into orbit - SSTO is no easy feat and requires some very fine flying... a good trip up with the current version will leave you about 3-5% fuel once you're circularized...

realistically, she's NOT capable of noseing up 70 degrees, then burning her way to orbital speed like we do on the DG... you gotta fly her slowly (mach 2) through the thick of the atmosphere - the first hypersonic transition should occur not lower than 20K Alt

otherwise, you waste too much fuel, and may not be able to reach a stable orbit

 

[Eccentrus]

well, try flying it with the keyboard please, the nose thinks that it's an occilator, hell, it flies more like a pendulum than a spaceplane (but then again, that image of a cowboy comes to the back of my mind crying , "Yeehaaaa..."), and I see 3 exhausts there, but I recon that it's still a single engined plane or is there actually a way to shift the engine?

And as always, great modelling there! :thumbup: looks like there are some improvements about the looks from before, and I like it

 

[Usquanigo]

Moach: Yes, I recall the discussion of not using LH2, and I am in full agreement that that is the way to go. And... funny thing is, a few months ago I called a friend of mine all excited, thinking that I had come up with something cool that would really lower cost of space flight, even potentially make SSTO possible, even if the only way of actually doing it was through orbiter. The idea was - why not simply open the nose cone of a rocket to let atmosphere in? Even if you aren't using the airborne O2 as an oxidizer, surely the air being heated and chucked out the back would act as extra reactant mass and thus improve thrust. You call them turbo-rockets. :thumbup: (sick minds think alike :lol: )

I simply mentioned metallic H2 in my previous post in reference to an earlier discussion of the XR2 where people were discussing how unrealistic it was since it was so tiny, yet SSTO and able to carry cargo to boot, and someone (Coolhand I think) said something to the effect of "maybe Altea cracked metallic hydrogen". And if such a thing were possible, then surely the XR-2 would be doable just as it is.

But I think of the real world proposals for SSTO and they are gi-normous, and almost entirely consisting of fuel. And I also think the hybrid system of "turbo-rockets" and scrams are the way to go. I'd even toss in turbojet, except that as has been pointed out, the weight cost doesn't really add up to an overall effectiveness.

Ultimately, I think something like the XL-70 concept or Burches Space Planes (where you have 1, or even 2 nested, winged launchers to get you up high and to scram speed, then you disconnect and go from there).

Either way, I'm not criticizing, just discussing.


Eccentrus: I have only a keyboard here at work and I bet you might be in the same boat, but... really, the pilots wouldn't be sitting there with their hands on a keyboard using the numpad to fly. Why should it be made overly gentle and safe just because we don't have or want to use a joystick? As I've said before, this is supposed to be a simulation, right? So if need be, I'll go home and use my $30 USB joystick and make it happen. If it was REALLY over the top, I might even consider using my Cougar for it, but so far, I don't use it for anything with Orbiter, it's for combat flight sims only (IL2, FS-WWI, SF2, LOMAC, etc). (would like to get a cheapy saitek rig, like the x45 or something for Orbiter (and B5:IFH), but can't spring for it right now)

 

[GuiConteDGIV2X]

and i think the normal bail out(ejection seats) is not good it s better a automatic ejection capsule with a heat isolant,automatic and economic hover motors and rcs so if you have a emergency on space you can simply deorbit and reentry and land verticaly like a

 

[Usquanigo]

and i think the normal bail out(ejection seats) is not good it s better a automatic ejection capsule with a heat isolant,automatic and economic hover motors and rcs so if you have a emergency on space you can simply deorbit and reentry and land verticaly like a

All those motors and shielding and fuel would add so much mass (and be so nose heavy), it would pretty much require a shuttle style vertical launch. (and even that doesn't have a jettisonable capsule)

Reminds me of the fiasco to make the F-111 a Navy Fleet Defense aircraft. The Navy wanted a capsule to eject and keep the crew safe in an emergency. That made the thing WAY too heavy to be anywhere near close to effective. Later, Grumman, who was contracted to build the F-111B (Naval version), said "we have a way to make a swing wing fighter for you that will meet all your requirements and do what you want and more" (having used the development of the 111B as research), and the F-14 was born.

...but I digress....

At most, there should be space suits and a UMMU paracone or several packed as cargo. But even better mght be that UCGO inflatable hab module. Just sit tight and wait for a rescue. Plus 1 will fit several people so it should cover the whole crew.

OR.... just focus on not having catastrophic failures and run with the danger (like the shuttle - even those problems were human error).

 

[Moach]

i guess sick minds really do think alike... do you also happen to have a most amusing case of adult A.D.D. like mine? :lol: - thank for Ritalin! :thumbup:

interesting you should mention the size of SSTO designs... the G42 is indeed larger than both the stock DG and the XR2 - measuring up to the less-remembered DeltaGlider-EX...


you really need that size in order to house up the needed amount of fuel... now, using ram air as both oxidyzer and additional propellant mass is what makes the whole concept work... otherwise, there's not much hope of avoiding a very frustrating water landing :hmm: