HyperDart - A new spaceplane

[T.Neo]

It very much would be needed. All spacecraft have them to disappate generated heat, as radiation is the only method of heat transfer in a vacuum.

That said, the radiators don't have to be functional, perhaps even just a texture on the inside of the payload bay doors. But they should not be overlooked.

 

[Usquanigo]

Venus round 2 eh? You argue just to argue. There are plenty of means of dealing with heat - including not generating so much that it matters, and also using the whole craft itself as a radiator (this was done by Heinkel even in '39), and those are merely 2 examples, there are still many more.

The fact remains that it is NOT an absolute requirement. Without knowing every detail of the internal systems you can not say that it's necessary. Only that you FEEL it should be there. I'm simply pointing out that it's an opinion on your part, not fact. Why turn this into an argument?

 

[halcyon]

Who's arguing? We're just discussing feedback on the addon.

To answer your responses:

What for?

That assumes that such cooling is actually necessary...I'm just saying the automatic assumption that it's needed, or that it would inherently add realism isn't correct...

In regards to a radiator, because I agree that it adds realism?
And no one said it was necessary. You're the only one to say the word necessary. Adding to realism doesn't automatically mean something is "necessary."

It should NOT be possible at ALL to get into orbit from the ground in the HD alone. If it can, that would suggest the ISP is probably a bit too high for the previously stated goal of near future realism.

You have to use the XL-70, take it to over M3.6 at 25Km alt, then launch the HD and head into Orbit. You can easily (too easily?) reach an orbit well into the 400s.

I never said I wasn't using the XL-70 in my tests. I know it's not possible to get into orbit from the ground in the HD alone.
I'm not doing that. My feedback was based off of using the XL-70.
And no I don't think it's easy for the average Orbiter user. The margin for error is too small.

Based on what research and data?

I don't mean to be a smart-ass, but honestly, statements like that beg that counter-question. It IS a challenge, and that's kinda the point. CigDriver has already said that he doesn't want to increase the overall temp threshold (and I agree with him), but that he will work on tweaking the heat build rate, slowing it down a bit, and also adding an air-brake.

You can't come crashing down like a capsule or a space shuttle, you have to fly it down, gently, slowly, keeping heat as low as possible.

Based on my testing?
Based on how I've seen other vehicles in Orbiter perform on reentry?
Why can't the HD have the same reentry profile as the shuttle? The shuttle takes a long time to reenter, slowly doing it's S turns to bleed off speed gently.
You think the HD should reenter slower then that? I had said I had redline temps at even a VS of -40 m/s. You consider that crashing down?

 

[CigDriver]

First off, calm down guys. This is supposed to be fun, not a pissing match

I'm amazed you got the PeA to 120! I never even get it positive on the main engines. I always have to switch to mr OMS engines. I'm pretty happy with how she gets to orbit. If the shuttle can't do it without an oms burn, I don't see it being a problem with the Dart.

I'll look into the heating. I can bump the convection rates a bit to lower the transfer rate.

 

[Tommy]

The HD is largely based on fifties tech. That means low margins for errors. This isn't a beginner's ship, by any means. It wasn't meant to be easy, but it's really not that difficult for an experienced pilot who understands orbits. The Main Engines, much like the SSMEs, aren't meant to get you into a circular orbit. They are to get your ApA established, with a high enough PeA that you can circularize with the OMS. By the time the HD gets that low on main fuel, it's accelleration rate becomes dangerously high, which realistically makes the switch to lower powered engine desireable.

As for the re-entry, the kind of unobtainium heat shields used on the DG type craft, or even the simple ceramic tiles used on the Shuttle would be available. This means a much lower heat tolerance than we are used to from vessels like the XR series or Shuttle. For a vessel like this, -40 m/s IS crashing down. -10 to 15 is appropriate. And altitudes will be much higher. Temp threshhold for a DGIV at 7.5 km/s is about 64k alt, in the HD it's close to 80k alt. Most of the aerobraking will occur at altitudes over 60k.

When I'm satisfied with my re-entry profile, I'll post a mini-tut.

 

[halcyon]

As for the re-entry, the kind of unobtainium heat shields used on the DG type craft, or even the simple ceramic tiles used on the Shuttle would be available. This means a much lower heat tolerance than we are used to from vessels like the XR series or Shuttle. For a vessel like this, -40 m/s IS crashing down. -10 to 15 is appropriate. And altitudes will be much higher. Temp threshhold for a DGIV at 7.5 km/s is about 64k alt, in the HD it's close to 80k alt. Most of the aerobraking will occur at altitudes over 60k.

If -40 m/s is crashing down, maybe this isn't the ship for me then.
Seems to me you can strike a balance between ultra realism and what's actually fun.
Solely my opinion.

 

[Tommy]

Fun is subjective. While I enjoy the XR series and DGIV immensly, re-entry in them has become a bit routine. I enjoy the challenge this ship offers, and trying to time things so the XL-70 isn't going into final approach at the same time the HD is reaching Apo. Even then I got into a 380k orbit with over half the OMS remaining.

The hard part of the re-entry is the initial decelleration. You'll need to keep the VS between -10 and -15 m/s for quite a while. By the time your velocity is down to 5.5 km/s you can use AerobrakeMFD to help choose the bank and AoA that will get you home. Small adjustmensts of COG , and plan your approach carefully. Speed management becomes crucial toward the end, there are no airbrakes yet, so you'll have to bleed off any excess speed with some fairly violent pitch-ups to increase the drag. Still haven't gotten one down to a safe landing, it's darn tough at the end.

 

[CigDriver]

Patch Time!
http://www.animatedexistence.com/orbiter/hyperdart/HD_PB3_Patch1.zip

Install over the public beta 3 linked a few pages back.

Changes:
Added a speedbrake to the HyperDart - hit "B", it might be a bit too effective!
Added HUD notations for both HyperDart and XL-70 when the speedbrake is deployed
Added gear notation to the XL-70's HUD
Changed the texture on the rotary knobs in the HyperDart. They now have white on the pointers for better visability
Changed the belly heating rate of the hyperdart, it heats much slower now, but also cools much slower, be careful!

I wanted to get this out, mainly for the temp stuff, but I need to fix a few more things. I noticed that the click zones for the roatry switches in the HyperDart are off a bit. I'll have to check into them again. This might be part of the problem people were having with them. I'll also add some type of animation for the HyperDart speedbrake. I'm thinking both rudders in and both elevons down. I'd also like to add a bit of control to the speedbrakes, instead of just on and off. Any suggestions on key combos for opening and closing them?

 

[T.Neo]

There are plenty of means of dealing with heat - including not generating so much that it matters, and also using the whole craft itself as a radiator (this was done by Heinkel even in '39), and those are merely 2 examples, there are still many more.

Uh, no. You can't get away from generating heat, and although the entire craft will (obviously) radiate heat away, you need an efficient system for removing heat from critical components (i.e. electronics).

And I somehow doubt Heinkel was building spacecraft in 1939.

The fact remains that it is NOT an absolute requirement. Without knowing every detail of the internal systems you can not say that it's necessary.

One does not need an engineering degree to deduce that spacecraft need to be cooled. The fact remains, that the spacecraft will need some means of radiating heat away from key components efficiently. And that means a radiator of some sort.

 

[CigDriver]

There are radiator textures on the bay doors. Open them once you are on orbit if it makes you feel better.

I could model some type of simple heat exchange. I already have the equations for the hull heating. The stuff I'm not sure about would be calulating when the craft is in sun, the radiated heat from terra, and how much heat is being generated by the electronis and people. That could be a lot of calculatons and a bit of reseach to figure out. I'm happy just thinking that they overall system is overengineered enough that if the bay doors are open everyhting remains cool enough

*edit
How about a two hour timer to get the bay doors open? If you pass that timer without opening the doors then all systems shut down just like if there are no ummus onboard.

 

[Tommy]

A quick check of the orbiter doc indicates that the core doesn't use the b or v keys, the could be used to increase/decrease speedbrake. Also, Home and End on the cursor pad could be used for COG shifthing if that doesn't have shortcuts yet. Will try the new version later tonight if I can. Thanks!

 

[halcyon]

Yes I second the suggestion to hotkey the CoG shifting. Ins and Del already do the trim, would be great to have CoG keys next to them.

 

[CigDriver]

Another patch:

http://www.animatedexistence.com/orbiter/hyperdart/HD_PB3_patch2.zip

copy the two .dll files over the old ones in your modules directory.

I added a speed-brake indicator to both HUDs. It shows the percent open when you have the speed-brake activated. "B" and "V" adjust the speed-brake in 10% increments, and must be pushed for each increase, you can't just hold it. I might change this, not sure yet. I also reordered the text indicators on the HyperDart HUD to put the speed-brake at the bottom so it matched the XL.

I also added the key commands for CoG shift. Page Up and Page Down adjust it. This is also not a repeating key. Since this is used for fine tuning I like it this way. I couldn't use "HOME" and "END" due to "HOME" being a core key, it resets your VC view. But, this allows separation between the two sets of adjustments and accidentally hitting the wrong key

I'm still playing with the idea of adding some form of system heating.

 

[Usquanigo]

Uh, no. You can't get away from generating heat, and although the entire craft will (obviously) radiate heat away, you need an efficient system for removing heat from critical components (i.e. electronics).

And I somehow doubt Heinkel was building spacecraft in 1939.



One does not need an engineering degree to deduce that spacecraft need to be cooled. The fact remains, that the spacecraft will need some means of radiating heat away from key components efficiently. And that means a radiator of some sort.

But one DOES need some imagination to apply understanding of principles to near future concepts (even if they are initially based on 50s and 60s era ideas).

You WANT it? Great. Don't sit there and claim it's required - it's not. And you are proving the point, you are arguing just to argue. I got busy last time and ended up having to let you go - don't make this thread drag off course. And while we're at it, let's not forget the dev side of things. CigDriver is doing and providing one HELL of a lot. Something like this should be at the bottom of the list, because anyone who's honest will admit that it's minor at best (and not even required).

While we're on that subject, it's a bit more likely to not have internal systems heat be a problem than it is to pack all that fuel on board, so if you want to nitpick, you're starting back to front anyway.

---------- Post added at 10:16 AM ---------- Previous post was at 10:14 AM ----------

Another patch:

http://www.animatedexistence.com/orbiter/hyperdart/HD_PB3_patch2.zip

copy the two .dll files over the old ones in your modules directory.

I added a speed-brake indicator to both HUDs. It shows the percent open when you have the speed-brake activated. "B" and "V" adjust the speed-brake in 10% increments, and must be pushed for each increase, you can't just hold it. I might change this, not sure yet. I also reordered the text indicators on the HyperDart HUD to put the speed-brake at the bottom so it matched the XL.

I also added the key commands for CoG shift. Page Up and Page Down adjust it. This is also not a repeating key. Since this is used for fine tuning I like it this way. I couldn't use "HOME" and "END" due to "HOME" being a core key, it resets your VC view. But, this allows separation between the two sets of adjustments and accidentally hitting the wrong key

I'm still playing with the idea of adding some form of system heating.

:speakcool:

Does this require the previously posted patch, or can this one simply be applied over the public beta?

 

[CigDriver]

You need the previous patch + beta 3. If you don't have the previous one (it is still on my server) you will only be missing the white lines on the hyperdart's rotary knobs. Not a big deal.

As for the heating...

If I put this in, I want to do it right. Not just "get in space and open the radiator and everything is always dandy" I'd want it to have function, not just a switch to remember to press. To do that I need to figure the heat the crew puts off, the heat from the systems (not only how much they make, but if they are on or off), the heat from the environment (radiated from earth and the sun) and possibly more. I'd also have to track when the panels are in the sun, both shaded from the earth and the ships itself. In the end all it is going to do is make you adjust your attitude every once in a while to get the panels to radiate better, or send someone of EVA for a few hours to help not produce so much heat in the ship. At this time, to me at least, it seems better to just assume the open bay doors do their job and everything is dandy. I'd rather spend the time coding the NAV radios I have on the dash. Perhaps in the future I'll put it in there.

Now, that being said, this is the end whether system heating should be included or not. I'm trying to get some feedback on how people think this thing handles. Move the debate to another thread, there was one in the add-on request thread a while ago where people were talking about what systems on a craft should be modeled, that seems like a great place for it. If it continues I'll ask a mod to step in.

As for flying this thing, I did a brief test and brought her out of a 290x290 orbit. I headed for KSC, dropping to a 290x70 orbit over northern Africa. The new heating rates allowed me to come in at -50m/s no problem. Down around 67Km at around M23 I was getting a bit hot on the wings so I took her back up to about 80Km and let her cool off on the trip up. I ended up passing KSC at about M12 at 50Km, a bit high and fast. I put her in a hard bank and turned her around. I ended up somewhere near Bermuda pointing back at KSC, looking good. A few blasts from the OMS to keep the speed up and I almost made it back. I ran out of OMS fuel at the worst possible time, and ended up in the Atlantic about 1 mile from KSC One of my better attempts at landing...I definitely need more practice:lol:

 

[Tommy]

Just tried the patch 2, no response for the keyboard COG. Page Up and Page Down are also used by the core, for adjusting the camera distance in external view. Darn it!

The new heat profile is definitely more friendly, managed to get it down from the ISS. Came in to high and fast so turned a big circle, ended up needing a bit of OMS. That was with patch one, the new variable speedbrake should help quite a bit. Will try it in a couple days, not enough time right now.

I did finally manage a deadstick re-entry in the unpatched beta. Took a few tries, and was a looooooong re-entry!

 

[halcyon]

I just tried patch 2.
While page up and down does increase/decrease view distance in external camera mode, it does in fact control the CoG in the VC.
Just like Cig said, you have to keep tapping the button, you can't hold it down like the trim.
The speed brake is great! I can land the bird no problem now, usually touching down around 155-160 m/s ground speed without collapsing the gear.

Still working on my reentries.

Edit:
Just noticed that when the engine mode selector is set to "off," you still hear the engine rumble when the throttles are engaged.
Is this something that's built into the core?

Suggestion:
For the speed brake animation, would you have to reconfigure the model to add a flap that comes out of the center of the back? Right in the middle of the body forward of the engines in the "no step" marked off area.
Each 10% increment could be distributed through 70-80 degrees of angle between the speed brake and the hull.
Just think of how the F-15C eagle has it's speed brake, shown below:

Also, do you plan on adding a mission timer/clock?

---------- Post added at 11:49 PM ---------- Previous post was at 07:12 PM ----------

Noticed another thing with the MFD screens themselves:

The top part of the screen on both MFDs is getting cut off. In the screenshot you can't see the plotted yellow dashed line for the prograde burn, and parts of the text are cut off also.
Is this fixable?

Also, I was just running Mission 5 - IMINT Satellite Intercept. I made a stable orbit of about 200km, fairly low eccentricity. Aligned planes with COSMOS2441, pulled up TransX (the newest version), plotted an intercept, then switched to the crosshair hud view showing countdown on when to make the burn and how much DeltaV to burn.

The countdown starts at 32k seconds, and when I accelerate time the sim ALWAYS crashes at the same time, 28.91k seconds to go.
I've tried different MFDs, different HUD displays, external/VC views combinations. It always crashes at that time.
I'll do more testing on another flight and see if I can reproduce the results after I do a fresh install of Orbiter.

 

[CigDriver]

I'll look into the engine sound issue. If I remember right (it has been like 8 months since I did that engine code!) I put in 0 thrust engine for the "OFF" setting for some reason. That would make orbitersound play a thrust sound when the engines are off. Since my programming knowledge is a bit better now perhaps i can eliminate that thruster.

It would take a pretty major rework of the model to add the speedbrake like you mention. It is a cool idea though. I'll think about it. BTW, that is a fantastic f-15 model! What company makes that? It looks like a 60 inch or so wingspan, BIG! I'd love to add that to my hangar

I never noticed the MFD issue. It is fixable, I just have to go back into the model and adjust the mapping for the MFDs.

I also made some changes to the RCS on the Dart. I lowered the thrust by almost half, it was just a bit too strong. I also lowered the amount of RCS fuel. I almost always landed with 75% still left, so I wanted it to be a bit more limited.

 

[Tommy]

COG is working, I wasn't paying attention and extracted to the base directory, rather than the correct modules directory. Opps!

There are a couple ways to deal with the engine sound issue. One is to reset the throttle to zero each step when the engines are off. Another is to use a custom engine sound (silence) when the engines are switched off (if using the zero thrust engine. Another is to give the engine a different propellent resource that is always empty when switched off.

 

[lennartsmit]

BTW, that is a fantastic f-15 model! What company makes that? It looks like a 60 inch or so wingspan, BIG! I'd love to add that to my hangar

If you click on the picture, it will get you to the site, after that searchfunction.
This is it:http://www.mikes-models.co.uk/index.php?main_page=product_info&products_id=3737

Keep your eyes closed for the price.