Power is Power and Speed is Speed, so what difference does direction make?

[BBP]

I know the weight of the plane and the pull of gravity will play a role in this discussion and some will laugh,    but here you go.
Why can a K-4 beat the pants off everything going vertical. Then you put it next to the La7 and 190-D and they blow its wings off in the horizontal. (WEP)Top End,(LA 381),(190-D 375), (K-4 368).
I don't know the Science but it seems to me a plane that can beat others in the vertical fighting gravity,(I know they all are) should be able to duplicate that performance in the horizontal against the others.
Its puzzling to me and I'm not a junior pilot in the ROTC training Corp. So can someone show me the light?

Thanks all,
KIMOSABE

[FLS]

Climbing is acceleration so the better climber also has better level acceleration even if it has a lower top speed. Very simply, top speed is thrust vs drag, climb rate is thrust vs weight.

[BBP]

So I guess you are saying its easier for Thrust to over come drag than it is to over come weight? Maybe I could see that.
But I like what you said that the better climber has better acceleration but will get beat over a longer distance by a plane going a fast speed for a longer time.
EG. A sprinter will beat a miler in the 100 yard dash, but the miler will catch the sprinter and beat him in the mile run. Now this makes sense to me.

Thanks Bro
KimoSabe

Psssst.......I shot Crabby down!

[streakeagle]

Lift to drag ratio. In a climb, you are fighting gravity, which is purely a battle of thrust to weight. In the horizontal turn fight, induced drag is your enemy => high wing loading and low aspect ratio => lots of induced drag compared to lower wing loading/higher aspect ratio fighters. Short stubby wings favor low zero-lift drag which is good for acceleration and vertical climbs, but allow a greater percentage of air to spill over the wingtips causing additional drag rather than generating lift.

With WW2 aircraft, the majority have similar plan forms (unswept wings and conventional tails), so basic numbers like aspect ratio and wing loading strongly determine relative performance differences especially at lower speeds. The missing parameters are the shape of the airfoils and the presence/efficiency of high lift devices like flaps and slats. At higher speeds, compressibility of air has an influence that varies with the design strategy.

Jet flight models are far harder to predict given the variation in geometry (delta, swept, trapezoidal, etc.) and higher speeds with transonic drag stability.

[FLS]

So I guess you are saying its easier for Thrust to over come drag than it is to over come weight? Maybe I could see that.

It's not "easier" for thrust to match drag. Drag increases with speed and/or lift until it balances thrust.  The point is that weight and drag are different enough that you can't use climb rate to predict top speed. You'll notice that as you burn fuel you climb better but your top speed in level flight does not increase.

[Karnak]

Spitfire Mk XVI and Bf109K-4 are an even more dramatic comparison.  They are neck and neck in climb for much of the spectrum, but the Bf109K-4 utterly demolishes the Mk XVI in speed:


La-7 vs Spitfire Mk XVI is probably the most dramatic divergence in speed and climb:


Bf109K-4 vs Spitfire Mk XIV isn't quite as dramatic:


And last Spitfire Mk XIV vs Spitfire Mk XVI:



As you can see, climb and speed are not completely associated.  To top both you need a powerful engine, but you can still attain great climb with a less powerful engine by minimizing weight.  That is how the Spitfire Mk XVI and Yak-3 do what they do on engines noticeably behind the more powerful DB605D, ASh-82FN, Griffon 65, R-2800-77(C) and Homare Ha-45/21 engines.

[Randy1]

Keep in mind too drag goes up dramatically with speed.  Noticed in the following equation the velocity is squared.

http://www.grc.nasa.gov/WWW/k-12/airplane/drageq.html

The same thing applies to you car or truck.  When you see those flying by you on the intrastate, you will know they are paying dearly for that in reduced gas mileage.

[GScholz]

As you can see, climb and speed are not completely associated.  To top both you need a powerful engine, but you can still attain great climb with a less powerful engine by minimizing weight.  That is how the Spitfire Mk XVI and Yak-3 do what they do on engines noticeably behind the more powerful DB605D, ASh-82FN, Griffon 65, R-2800-77(C) and Homare Ha-45/21 engines.

The Spit16 and 109K are actually very similar in weight and power. 1720 hp Merlin vs. 1775 hp (1800 PS) DB. The Spit trades speed for maneuverability with those bigger wings, that's about it.

[Cthulhu]

Lift to drag ratio. In a climb, you are fighting gravity, which is purely a battle of thrust to weight. In the horizontal turn fight, induced drag is your enemy => high wing loading and low aspect ratio => lots of induced drag compared to lower wing loading/higher aspect ratio fighters. Short stubby wings favor low zero-lift drag which is good for acceleration and vertical climbs, but allow a greater percentage of air to spill over the wingtips causing additional drag rather than generating lift.

With WW2 aircraft, the majority have similar plan forms (unswept wings and conventional tails), so basic numbers like aspect ratio and wing loading strongly determine relative performance differences especially at lower speeds. The missing parameters are the shape of the airfoils and the presence/efficiency of high lift devices like flaps and slats. At higher speeds, compressibility of air has an influence that varies with the design strategy.

Jet flight models are far harder to predict given the variation in geometry (delta, swept, trapezoidal, etc.) and higher speeds with transonic drag stability.

Hey streakeagle, you don't happen to work on Sand Lake Rd in Orlando do you? 

[streakeagle]

I live in Orlando, but I work in Kissimmee for the Toho Water Authority. I go to Sand Lake Rd sometimes to get to theme parks and/or stores/restaurants. Why do you ask?

[Cthulhu]

I live in Orlando, but I work in Kissimmee for the Toho Water Authority. I go to Sand Lake Rd sometimes to get to theme parks and/or stores/restaurants. Why do you ask?

Just wondered. You seem to know your stuff. Our sister facility (Lockheed  Martin Missiles & Fire Control - Orlando) is there.

[BaDkaRmA158Th]

Direction matters a lot.



All the power and speed in the world wont help you if your going nose down into the ground.