Grumman Rules the Sky

[J.A.W.]

 Yeah, funny - coz just like the guys on this thread,
 - M.J. could not admit his `51H stick time was ..

..ZERO..

& just like when a proposed TEST is discussed here, he too fell back on a big noting rant..

As if ego beats science..  ..L.O.L...

Unless, maybe.. you mean for  'hot air balloon'  lift/thrust.. ..L.O.L...

He didn't run an F8F at Reno this year either.. not that he won.. anyhow..

But a `51 did...

[Golfer]

So all this is for you is insisting the P-51H is the epitome of awesome and no radial engine powered Ironworks airplane could ever best it in performance and going "LALALALALA" with your fingers in your ears when evidence is given otherwise.

Check.

Moving on.

[Karnak]

J.A.W.,

Do you agree that the faster an aircraft travels through the air the greater its parasitic drag becomes?

[B3YT]

sorry for being late to the party but wouldn't a head wind decrease rate of climb as it would cause turbulence in the airflow over the wing at high angles of attack?  as the head wind hits the leading edge it would  swirl over top wing surface disrupting the airflow  effectively bringing on stall like characteristics? with out a head wind the air would pass over the top surface parallel to the path of the aircraft providing a smoother flow of air that generates the lift?  please kanark correct me if I'm wrong .   

[WWhiskey]

The only reason I could think of to bring that fight here, would be have the P-51h and the F8F modeled in game so you could see the test recreated but both of them did not see combat so they would not be modeled here?
Since there are only 2 P-51H's still airworthy,, maybe your time would be better spent trying to get now of them up to try it out.

BTW. Since the H is such a hot rod build instead of an advanced D model,,, basically a new plane,,, why did the U.S. Send P-51D's to Korea, instead of the all powerful H?

[J.A.W.]

See Rule #4

[Golfer]

Great.  You win.

Go break the record with a 51H.

[Golfer]

I used the space shuttle as an example of showing you that you don't know with any level of certainty what you're speaking of.  The fact you equate the fabric thermal protection covering to body armor shows your ignorance.

You didn't connect the dots

There's a difference between you and I. When I learned the shuttle was covered in fabric I shut my mouth and listened to something someone with experience was telling me.

[WWhiskey]

Yeah, funny - coz just like the guys on this thread,
 - M.J. could not admit his `51H stick time was ..

I read that thread to the end and not once did I see mention of his stick time in an H

I did see a question asked by him tho that peaked my interest.   I'll paraphrase,,, if the pony could have,, why hasn't one done so?  It's been plenty long enough for someone to prove,, yet Rare Bear still stands alone,,
And that's a fact Jack!

[Brooke]

& it seems you don't read the posts either Brooke..

I read them.

Either that or you simply ignore those which run counter to your assumptions..
..or what you 'believe' - as FLS puts it..

Do the maths lie?

Got any proof via scientific formulae?

Otherwise opinions are fine.. but weak.. as evidence, even 'logic' - don't cut it against maths..

& same goes for ol' mans empirical/experiential opinions, since he hasn't actually done
a climb which matches the parameters of the stunt, obviously..

These are aspects of basic physics and basic aerodynamics.  The equations in aerodynamics (thrust, lift, drag, etc.) depend on speed of the aircraft through the air, not on the speed of the air relative to anything else.  That's why if you put a wind tunnel in a train car and tested a model while the train is at rest, you would get the same results as if the train car were moving along at a steady 30 mph.  This is the concept in physics of a reference frame.

Here is an equation for rate of climb in reference frame of the air that the aircraft is traveling through:  ROC = (T - D) * v/W, where T = thrust, D = drag, v = velocity of aircraft through the air (relative to the air it is travelling in), W is the weight of the aircraft.  D = 0.5 * rho * v^2 * S * C_D, where rho = density of air, S = wing area, C_D = coefficient of drag.  T = eta * 375 * gamma * BHP / v, where eta is propeller efficiency, gamma is a factor for how much of full power is being applied (1.0 for full power, 0.5 for half power, 0 for no power, etc.), and BHP is the brake horsepower of the engine.

By high-school physics, here is an equation for rate of climb in air moving relative to the ground (i.e., in ground's reference frame), choosing a reference frame with y direction perpendicular to ground and x direction parallel to ground and with an arbitrary wind velocity vector (v_x, v_y):  ROC_withwind = ROC + v_y.  This is high school physics.  Note now that ROC is independent of v_x and v_y, and thus that ROC_withwind depends on v (speed of aircraft through the air, independent of what the speed of that air is relative to the ground) and on v_y (the speed of the air perpendicular to the ground, such as updraft or downdraft), but is completely independent of v_x (speed of air parallel to the ground, such as headwind or tailwind).

There are lots of references online on such things.  Here's one among many for the math of ROC:  http://www-mdp.eng.cam.ac.uk/web/library/enginfo/aerothermal_dvd_only/aero/perf/climb/.  For basic physics, there are lots of books -- just look in Amazon and they will have many.  For an introduction to aerodynamics, I like "Introduction to Flight," by John D. Anderson, Jr.

[ink]

obviously you guys have never heard the old saying......"cant fix stupid"

[Brooke]

I like debating things on the forum.  I'm not expecting to change anyone's mind, though -- that's not what I expect to get out of it.

[J.A.W.]

WW, it aint about 'stupid' as ink claims..( 'stupid' claim, really)

It comes down to Cubic $.. ..which is why R-B is past its best-by-date Reno race results-wise too..

&that R-B FAI record has lapsed..

I sure did ask M.J. about `51H stick-time.. he simply could not admit it.. he had zip..

WW, an A-H  F-51H vs F8F-2 showdown based on those mil-spec test fihures could be cool, good idea..

[J.A.W.]

I read them.

These are aspects of basic physics and basic aerodynamics.  The equations in aerodynamics (thrust, lift, drag, etc.) depend on speed of the aircraft through the air, not on the speed of the air relative to anything else.  That's why if you put a wind tunnel in a train car and tested a model while the train is at rest, you would get the same results as if the train car were moving along at a steady 30 mph.  This is the concept in physics of a reference frame.

Here is an equation for rate of climb in reference frame of the air that the aircraft is traveling through:  ROC = (T - D) * v/W, where T = thrust, D = drag, v = velocity of aircraft through the air (relative to the air it is travelling in), W is the weight of the aircraft.  D = 0.5 * rho * v^2 * S * C_D, where rho = density of air, S = wing area, C_D = coefficient of drag.  T = eta * 375 * gamma * BHP / v, where eta is propeller efficiency, gamma is a factor for how much of full power is being applied (1.0 for full power, 0.5 for half power, 0 for no power, etc.), and BHP is the brake horsepower of the engine.

By high-school physics, here is an equation for rate of climb in air moving relative to the ground (i.e., in ground's reference frame), choosing a reference frame with y direction perpendicular to ground and x direction parallel to ground and with an arbitrary wind velocity vector (v_x, v_y):  ROC_withwind = ROC + v_y.  This is high school physics.  Note now that ROC is independent of v_x and v_y, and thus that ROC_withwind depends on v (speed of aircraft through the air, independent of what the speed of that air is relative to the ground) and on v_y (the speed of the air perpendicular to the ground, such as updraft or downdraft), but is completely independent of v_x (speed of air parallel to the ground, such as headwind or tailwind).

There are lots of references online on such things.  Here's one among many for the math of ROC:  http://www-mdp.eng.cam.ac.uk/web/library/enginfo/aerothermal_dvd_only/aero/perf/climb/.  For basic physics, there are lots of books -- just look in Amazon and they will have many.  For an introduction to aerodynamics, I like "Introduction to Flight," by John D. Anderson, Jr.

Sure, & thanks for the efforts there Brooke..

Anyone recall the ol'  'Bumblebee' test.. back in the day,  & according to the - then -  current physics theory..

The B.B.  couldn't possibly fly.. but the B.B. knew better.. & he had flight tests as proof..

[WWhiskey]

The ultimate world record for a climb to 3,000 meters stands at 91.6 seconds, set in 1972 by Lyle Shelton in a modified Grumman F8F Bearcat.


FIA or not,, that is still the holly Grail, unless you know of another piston propeller plane that has done it faster?