HVAR recoil

[Destroyer37]

Chuck Yeager responded to a message I sent him yesterday.

 

Quote From (Ret Gen) Chuck Yeager- "No Kick"

Edited July 17, 2015 by Destroyer37

[Destroyer37]

Which professional airmen stated this? You guys scoffed at me wanting to try and find a pilot like ED has for the German planes, but we are back to a line from the manual again? I think I am done with this thread, I can do my own (and currently am) research.

 

Chuck Yeager.

[Tucano_uy]

..

[msalama]

Chuck Yeager- "No Kick"

 

:thumbup: Right-o, seems to be wrong in DCS then.

[Destroyer37]

Simply that Chuck Yeager answered a forum question, even if indirectly, is the awesome-sauce squared :clap_2:

 

I'll post a screen cap of the email I sent him yesterday it was indirect in the sense that he didn't answer here but it was a direct answer to the question I sent him because of this thread so sort of pseudo direct!

[NineLine]

Awesome, good to know he will answer occasionally :) Pretty decent source ;)

[Destroyer37]

Awesome, good to know he will answer occasionally :) Pretty decent source ;)

 

 

Agreed glad I thought to ask him.

[NineLine]

Agreed glad I thought to ask him.

 

You and 20 other people ;)

[Destroyer37]

This is a screen shot of the message I sent yesterday. Old news now, but still pretty cool that he replied.

[SmokeyTheLung]

That puts that one to bed. Nice!

[eurofor]

Great :thumbup: anyone feel like arguing with Chuck Yeager on this subject?

[NineLine]

Great :thumbup: anyone feel like arguing with Chuck Yeager on this subject?

 

Depends, can anyone confirm he really said he could see 109 flying over Berlin from the English Channel? :P

[IonicRipper]

That puts that one to bed. Nice!

 

Question is, will ED change this behavior?

[streakeagle]

Releasing a rocket should be little different than releasing a bomb. The key difference is that the rocket is not only accelerated by gravity, but its own propulsion. As long as the rocket is free to fly off the rail before ignition, the thrust should have little impact on the aircraft...

 

But, there used to be a rocket hanging there exerting drag under the wing. The exhaust from the rocket might also create some turbulence in the air flowing over the wing as it pulls away. But would these effects be strong enough for the pilot to notice them?

 

Each HVAR rocket weighed about 134 lbs. Would dropping a single 134 lbs bomb off of either wing mount of a P-51D have caused any perceivable forces on the aircraft? I am going to make an informed guess that it would not.

 

Chuck Yeager's "no" makes sense. In an aircraft already loud and vibrating, whatever forces firing an HVAR might induce on the aircraft would tend to be imperceptible.

[Exorcet]

The exhaust from the rocket might also create some turbulence in the air flowing over the wing as it pulls away. But would these effects be strong enough for the pilot to notice them?

Slightly different application, but the effect of exhaust over a surface is the kind of thing banned from auto racing because it makes cornering speed scary fast due to the amount of downforce produced.

 

Aero force grows with V^2, so double speed doesn't double lift/drag, it quadruples it. The rocket exhaust plume will be very fast. The rocket doesn't stay near the wing very long, but there is some potential for affecting the launch platform's aerodynamics.

[ShuRugal]

Aero force grows with V^2, so double speed doesn't double lift/drag, it quadruples it. The rocket exhaust plume will be very fast. The rocket doesn't stay near the wing very long, but there is some potential for affecting the launch platform's aerodynamics.

 

on paper, you might be able to calculate a difference in aerodynamic forces due to the exhaust plume. In practice, it's going to be completely negligible. the exhaust stream is a whole two inches wide, is not aligned so it will interact with the wing while still moving at any appreciable speed compared to the surrounding air, and only interacts with the wing for a tenth of a second at most. Amazingly out of the park best-case scenario: exhaust plume adds 200lbs of lift for half a second to a wing already producing in excess of 2 tons of lift, on an aircraft weighing in at 4 tons, and the pilot doesn't notice the jerk because he's already maneuvering hard through choppy low-altitude air.

[Exorcet]

I wouldn't expect a big effect, mostly because I don't think the wing sees enough change in airflow (as you said the plume isn't aligned to really hit the wing).

 

I do want to hear ED's reasoning for the recoil though as I'm interesting in what they think would cause the reaction on the P-51. I can think of some things that could potentially cause the plane to react, but nothing truly convincing.

[Destroyer37]

The question remains, do you think ED will head the comments of a seasoned combat aviator and test pilot with real world experience, or will we continue to have the misrepresented rocket model forever? I personally think it could go either way, should be interesting to watch though! Looking forward to more discussions, and less red squares!

[RAZBAM_ELMO]

Baaazinga

[Random]

I really hope this means it'll get removed but I have a hunch that they won't accept pilots anecdotes/recollections as evidence as per many other discussions. Even though one of the gods of aviation said it.

[Narushima]

I really hope this means it'll get removed but I have a hunch that they won't accept pilots anecdotes/recollections as evidence as per many other discussions. Even though one of the gods of aviation said it.

 

They're staying quiet for now, which probably means they're looking into it.

[msalama]

won't accept pilots anecdotes/recollections as evidence

 

And they shouldn't either, because recollections are imprecise. But let's still say that Yeager's comment strongly supports the notion of there being something wrong with our rocket modelling. Anyway, I'm pretty certain this will be looked at in due course...

[Random]

And they shouldn't either, because recollections are imprecise. But let's still say that Yeager's comment strongly supports the notion of there being something wrong with our rocket modelling. Anyway, I'm pretty certain this will be looked at in due course...

 

The problem is that the real things manuals say no recoil too and thats been discounted as "unreliable". What would be acceptable proof?

[Destroyer37]

The problem is that the real things manuals say no recoil too and thats been discounted as "unreliable". What would be acceptable proof?

 

Before we make any more accusations we should wait it out and see if they fix it. Lets give ED the benefit of the doubt and assume they didn't have the information they have now when they made the model. Lets see what happens. If it isn't fixed at that point then maybe we can ask that question again...what do you think?

[NineLine]

The problem is that the real things manuals say no recoil too and thats been discounted as "unreliable". What would be acceptable proof?

 

First, nobody has discounted anything as unreliable. Its simple stated that when you have an engineer who knowns the effects of certain things, such as rockets, its fair to question other sources. So the manual wasnt enough to completely disprove what we have modelled. Knee-jerk changes wont get us anywhere.

 

Mr Yeager was kind enough to answer a number of people on a question of recoil of the rockets. As well, I have requested a number of documents on development and testing of the HVAR rockets which I am still waiting on. Once we can gather all that, we can determine the best course of action.

 

Realize that this probably wont be a priority fix, it wont come out till after or during the 2.0 release if a fix is deemed necessary. It may depend on how long it takes to get these new docs. So be patient and dont get carried away with conspiracy theories about ED not wanting to change HVARs, it just has to go through the standard processes.