HVAR recoil

[NineLine]

the recoil-free behaviour of i.e. Mavericks (even bigger "rockets" than HVARs) is not considered relevant.

 

 

SO you would suggest that we should base a 1944 HVAR on the Maverick? That is good evidence? I would hope the launchers and such have improved since 1944... but I am no expert....

 

Yo-Yo showed the video to explain you can have a 'recoil' effect withrockets, he hasnt said that this is what the DCS P-51 is modeled after (in fact he is very open to looking at the issue).... so are you saying the US had the same rocket tech back then as they do now with modern missiles?

[Destroyer37]

I was wondering why the HVAR recoil behaves the way it does, pushing back on the wing fired from an down on the nose. This is the sort of behavior a cannon would exhibit. The rocket exhaust gasses don't push against the plane, only the air. Firing a free-hanging rocket should produce almost no recoil. Of anything, it would pull the wing forward slightly until the retention force of the rack was overcome.

 

My question was directed at your source of information. It implies that some kind of acceleration (no recoil) is happening when using the HVAR rockets.

 

 

 

 

Thx, I started reading. The video clips still show nothing significant to me. Will continue to read but if you like I have no problems with spoilers telling me that you see no recoil. I never claimed that!

 

From my point of view as a prop pilot and certified biophysicist I would stick with the OP theory.

 

And just to be clear I agree with the OP, there should be a forward pull if anything, certainly not recoil.

[FSKRipper]

And just to be clear I agree with the OP, there should be a forward pull if anything, certainly not recoil.

 

Fine, then were are on the same track. But even with my physics background, I'm far away from understanding events like airflow disturbance on a wing by missiles fired from this wing. :cry:

[Flagrum]

SO you would suggest that we should base a 1944 HVAR on the Maverick? That is good evidence? I would hope the launchers and such have improved since 1944... but I am no expert....

 

Yo-Yo showed the video to explain you can have a 'recoil' effect withrockets, he hasnt said that this is what the DCS P-51 is modeled after (in fact he is very open to looking at the issue).... so are you saying the US had the same rocket tech back then as they do now with modern missiles?

No. I am asking what weapon we see in that video, to better understand why the platform is affected by it. Just because it utilizes a rocket motor type device is obviously not enough - as other weapons of this definition seem to be considered as not really comparable enough ...

[Random]

Thought: Can you fire rockets while on the ground? I think I've done it and I think I didnt shoot backwards several feet. I'm quite possibly mistaken, bad memory.

 

Anyone fancy testing that? I'm away from home for a couple of days.

[RAZBAM_ELMO]

Just to put some 2 cents in here. if you re-watch the videos posted by Yo-Yo on the launchers on small pick ups, I dont know about you but If I were to launch a rocket, motar or whatever it maybe I would launch it from the longitudinal axis rather than the horizontal. Clearly you can see from the jeeps firing rockets theres barely any movement from the jeep which is lighter than the pickups. Why? Because its fired from the longitudinal axis of the jeep offering more stability than firing them from the side if the pick-up. WHHHIIICCHHH now brings me to the mustang. Now I don't fly the mustang, nor will I, but thinking with our physics cap on here for a minute. If we were to fire a rocket with x thrust which is traveling in the same longitudinal direction at say 500 km/H ( yeah sorry Canadian problems) then I can think of no way that this would have the seen "recoil" effect upon the aircraft. Now I'm not an engineer, nor a pilot from the 40's but I can see this is getting a bit out of hand here guys. Rather than bash Yo-Yo and ED for their supposed silly FM why don't we work as a team and as a community to help improve and assist each other with this dilema? Sorry for the banter but I don't want to see people angry at each other for a simple 127mm HVAR.

[johnv2pt0]

This problem of hvar "recoil" has always bugged me too. A couple of things I've noticed in this discussion and a tidbit from personal experience.

 

There is official documentation stating the absence of recoil...specifically highlighted for superior performance of such a weapon fired from an aircraft.

 

All the guncam footage I've seen of hvars being fired from WWII aircraft show no recoil.

 

No guncam footage has been provided showing any recoil. The only "evidence" of this recoil has been from different weapon systems mounted on different vehicles. Not really an apples-to-apples comparison.

 

Shouldn't that be enough evidence? I mean I don't see why this is even a long debate unless it's to defend ED's programming honor or something. Nobody is out to get ED and nobody is denying the awesomeness that is DCS. I've read this a just constructive criticism to get the most realistic experience possible...not to dumb it down.

 

Now, for personal experience: I was a USAF pilot, so I am familiar with how documents are written and why things are worded certain ways. It's a very precise language...everything is precise. Heck, the boldface pilots have to learn and write down is required to be identical...down to the hyphenations, case of letters, and even a typo if it was in boldface your were given. If the manual says "there is no recoil," then there is no recoil. That's not really language that leaves a lot to interpretation.

 

The only wiggle room I will give this is that the Air Force wasn't even a thing yet, so perhaps the writing of documents improved over the years. That said, I highly doubt something so gross as this could be the case.

 

Just my .02 and my experiences...YMMV

 

 

Oh, just found this beauty. Debate closed: no recoil on a remote control Mustang firing bottle rockets. :megalol:

 

[Tucano_uy]

Shouldn't that be enough evidence? I mean I don't see why this is even a long debate unless it's to defend ED's programming honor or something. Nobody is out to get ED and nobody is denying the awesomeness that is DCS. I've read this a just constructive criticism to get the most realistic experience possible...not to dumb it down

 

+1

 

And this issue is not the only example of this mindset. Think of the missile performance topic, the rocket effectiveness issue years ago, etc, etc.

 

I guess we are the clients, and we vote with our wallets. Take it or leave it. So far I'm still buying.... :joystick:

[Captain Orso]

*sigh* :(

 

You know what is really difficult, and understandably so? Knowing that gut-feelings arguments (beliefs)1) have no relevance, because they are merely thoughts which are often demonstrated to be monumentally wrong. But damn they sometimes feel so right. That's what it means to be human.

 

What the OP, or anybody else for that matter, believes on this subject is meaningless beyond a human level where it sparks interest and discussion.

 

There is no proof in nature --the real-world-- there is only evidence. There is no proof of gravity, there is only evidence of its existence through experiments.

Drop an apple. Did it fall?

Do it a second time. Did fall again?

Do it one hundred times, -one thousand times, -one million times. Did it fall each time?

Gravity is still a scientific theory and not proven.

 

Demonstrations (videos) of the affects of firing some-type of rocket from a tube mounted on a small truck is evidence of something.

 

Demonstrations of the affects of firing a Hellfire rocket from an AH-64 helicopter is evidence of something.

 

But in both cases the evidence is indirect and disputable, because the subject of the evidence is not the subject of the discussion.

 

A conjecture has been made, that the written, documents from several sources provided as evidence in this thread are less than dependable, with one claim that written documentation is in general not reliable. This is to some extent true, in that what is written, was written by a person, and persons are prone to make mistakes.

 

However, there is a great difference between a document simply written by somebody on a piece of paper and a document reviewed by an internal organization and then published, at which time then becomes subject to public scrutiny and critic.

 

It has been suggested that a person who has had the personal experience of flying P-51D's and firing HVAR's be consulted to bring personal testimony.

 

Two organizations have already gathered this testimony and published it in the P-51D flight manual and the document provided by Holbeach from the Ordnance School Aberdeen Proving Ground Maryland, 1944. This is not only testimony, but testimony by professionals and experts which has been subject to review by before being published.

 

1) Belief: confidence in the truth or existence of something not immediately susceptible to rigorous proof.

[Destroyer37]

Bravo, Captain Orso very well said. So with all of this should we expect to see in some reasonable amount of time a correction made to the rocket flight model in DCS?

[NineLine]

Bravo, Captain Orso very well said. So with all of this should we expect to see in some reasonable amount of time a correction made to the rocket flight model in DCS?

 

You should expect it to be looked at, which it is being looked at. It hasnt been determined what fix might be required yet.

[Destroyer37]

You should expect it to be looked at, which it is being looked at. It hasnt been determined what fix might be required yet.

 

Thanks.

[Captain Orso]

Like Christmas in July :thumbup:

[SmokeyTheLung]

 

Here's an interesting few clips. Unknown aircraft and weapons. As far as I can tell the pilot(s) are firing single rockets instead of pairs, which seems quite rare going by gun camera archives (it's sometimes hard to tell because of the placement of the gun camera). Maybe you can get some information from watching.

 

Check out 4:02 and 2:43

[zaelu]

I don't know if we should see a recoil when firing HVARS with P51 but those gases expanding from rocket engine from launch and well beyond rocket leaves the plane shouldn't have some aerodynamic effect?

 

I'm thinking at those:

 

-gases expanding under wing increasing lift (only for a free suspended rocket and not one in tube)

-gases expanding against horizontal stabilizer and wing

-rocket engine burning in front of wing and horizontal stabilizer creating disturbances in airflow thus increasing drag on that side

 

 

All modern plane shake a bit when launching a missile in YT videos and sometimes you can see wing tips flapping.

 

Also the P51 had a CoG a bit aft (iirc) and this could favor a bit of instability in such situations?

[Destroyer37]

 

Here's an interesting few clips. Unknown aircraft and weapons. As far as I can tell the pilot(s) are firing single rockets instead of pairs, which seems quite rare going by gun camera archives (it's sometimes hard to tell because of the placement of the gun camera). Maybe you can get some information from watching.

 

Check out 4:02 and 2:43

 

Judging by the other allied aircraft in the cam I would say that there is a high probability that this footage is in fact from a P-51D in the PTO. I am also seeing single launches of rockets, with no apparent recoil.

[NineLine]

Judging by the other allied aircraft in the cam I would say that there is a high probability that this footage is in fact from a P-51D in the PTO. I am also seeing single launches of rockets, with no apparent recoil.

 

I am seeing some vibration in the camera when the rockets are fired, doesn't look like the guns are being fired at the same time. SO its possible something is going on when the rockets are launched.

 

Also at 2:43, is it just me, or does the plane sway forward with each rocket launch?

Edited July 16, 2015 by NineLine

[Destroyer37]

I am seeing some vibration in the camera when the rockets are fired, doesn't look like the guns are being fired at the same time. SO its possible something is going on when the rockets are launched.

 

Starting at 4:02 guns and rockets are firing, check out the building in the back ground. Recoil from a single .50 M2HB is 500lbs of back pressure. That's what is shaking the plane. Not the rockets. Fact.

[Yo-Yo]

 

Here's an interesting few clips. Unknown aircraft and weapons. As far as I can tell the pilot(s) are firing single rockets instead of pairs, which seems quite rare going by gun camera archives (it's sometimes hard to tell because of the placement of the gun camera). Maybe you can get some information from watching.

 

Check out 4:02 and 2:43

 

Do you mean 2:47? I see very pronounced yaw during the launch.

[Destroyer37]

Do you mean 2:47? I see very pronounced yaw during the launch.

 

I see the yaw you are seeing however if you reference the follow up shots of 2 there is no yaw whatsoever which makes me think that the pilot was hitting his rudder to get onto target at the last second.

[NineLine]

Starting at 4:02 guns and rockets are firing, check out the building in the back ground. Recoil from a single .50 M2HB is 500lbs of back pressure. That's what is shaking the plane. Not the rockets. Fact.

 

I am not sure the initial shots hitting the building are from the same plane, the the shaking is pretty consistent to the rocket launch...

[rcjonessnp175]

Yup good old 50 will vibrate the fillings out your teeth. I imagine their is some sort of an effect on the airframe when the weight of those rockets come off. Aka need to compensate for the uneven weight distribution on the airframe. One thing we all need to keep in mind is the hvar rocket is quite large.

[Destroyer37]

I am not sure the initial shots hitting the building are from the same plane, the the shaking is pretty consistent to the rocket launch...

 

Pretty consistent to six fifties from what I can tell.

[NineLine]

Yup good old 50 will vibrate the fillings out your teeth. I imagine their is some sort of an effect on the airframe when the weight of those rockets come off. Aka need to compensate for the uneven weight distribution on the airframe. One thing we all need to keep in mind is the hvar rocket is quite large.

 

Yeah, my gut tells me there has to be something going on when the rocket comes off the rails... but I have no real world experience to say yay or nay...

[NineLine]

Pretty consistent to six fifties from what I can tell.

 

I am not seeing that many hits to the building, and again, the vibration starts when the rockets is released and stops shortly after (and repeats on the second lanuch)... we can guess its guns going off at the same time, but we are back to personal interpretation...