Holding the energy

[Debrody]

Some planes hold the energy well, some dont. I would like to know which factors are inportant in a good energy retention rate. Thank you 

[ACE]

Be easy on the 

[Debrody]

lol you can pull a 152 as hard as you can and it will still remain fast, try the same in an earlyer 190...

[ACE]

You asked.

[MachFly]

You mean which factors are important in the airframe for an aircraft to hold energy (from an engineering perspective)?

It primarily depends on the type of wing you have (and the wing loading). For example if you take a spitfire and accelerate it to ~500mph it will bleed off that energy quickly, but if you have it maneuver at ~300mph it will maintain it's energy a longer than most other planes (190 in this case will do the opposite).   

[EskimoJoe]

I believe the primary factor would be the thrust/weight ratio.

*edit See Bozon's post below, very informative!   

[bozon]

Inertia is maintained better by high mass/drag ratio: drop a hollow plastic ball to the ground, then repeat the experiment with ball filled with water/sand. Guess things do not fall to the ground at the same speed like we heard in school... This is an important effect in holding straight line high speed gained after a dive. The mosquito is probably the highest mass/drag plane in AH set.

High thrust/drag ratio does not hold the energy, but instead replenish it giving a net effect of slower energy bleed. Spit 14, 109K, La7 are pretty good in this department.

Low wingload helps to lower the induced drag in a given turn (vs. the same turn with smaller wings on the plane). However, induced drag is important only in high angle of attacks and a larger wing will have more parasitic drag which dominated at high speed/low angles of attack. Lightly loaded planes will tend to hold E better in a turn, while high loaded planes will tend to hold E better in a high speed straight line after a dive.

Perhaps some other factors I forget.

[FLS]

High aspect ratio wing has less induced drag.

[Plazus]

Inertia is maintained better by high mass/drag ratio: drop a hollow plastic ball to the ground, then repeat the experiment with ball filled with water/sand. Guess things do not fall to the ground at the same speed like we heard in school... This is an important effect in holding straight line high speed gained after a dive. The mosquito is probably the highest mass/drag plane in AH set.

High thrust/drag ratio does not hold the energy, but instead replenish it giving a net effect of slower energy bleed. Spit 14, 109K, La7 are pretty good in this department.

Low wingload helps to lower the induced drag in a given turn (vs. the same turn with smaller wings on the plane). However, induced drag is important only in high angle of attacks and a larger wing will have more parasitic drag which dominated at high speed/low angles of attack. Lightly loaded planes will tend to hold E better in a turn, while high loaded planes will tend to hold E better in a high speed straight line after a dive.

Perhaps some other factors I forget.

^ Pretty much nails it on the head. Energy retention has different meanings to different aircraft, as bozon describes above. Understanding how an aircraft retains its energy is crucial in a dogfight.

I like to think that energy fighting is a lot like manipulating an aircraft's momentum. Like a pendulum swinging from one spot to the next. It's a dance of trading speed and altitude back and forth in order to shoot down your opponent.

[drgondog]

Some planes hold the energy well, some dont. I would like to know which factors are inportant in a good energy retention rate. Thank you 

Maybe two discussions - one is 'retaining/maintaining energy once gained' which is a discussion more about drag, and except for high CL (and Induced Drag) is about Parasite Drag and Viscous drag due to Lift.  All things being equal an a/c which has a higher Aspect ratio will have less Induced Drag

Two is 'regaining energy once lost' which is a discussion invloving several factors.  To name a few is thrust to weight ratio, zoom climb characteristics (which is a combination of CL and drag and W/S)

[SEseph]

Inertia is maintained better by high mass/drag ratio: drop a hollow plastic ball to the ground, then repeat the experiment with ball filled with water/sand. Guess things do not fall to the ground at the same speed like we heard in school... This is an important effect in holding straight line high speed gained after a dive. The mosquito is probably the highest mass/drag plane in AH set.

High thrust/drag ratio does not hold the energy, but instead replenish it giving a net effect of slower energy bleed. Spit 14, 109K, La7 are pretty good in this department.

Low wingload helps to lower the induced drag in a given turn (vs. the same turn with smaller wings on the plane). However, induced drag is important only in high angle of attacks and a larger wing will have more parasitic drag which dominated at high speed/low angles of attack. Lightly loaded planes will tend to hold E better in a turn, while high loaded planes will tend to hold E better in a high speed straight line after a dive.

Perhaps some other factors I forget.

Very informative. 

The theory that everything falls at the same speed only applies to objects in a total vaccuum.

[Blooz]

Very informative.  

The theory that everything falls at the same speed only applies to objects in a total vaccuum.

Yup.
http://www.youtube.com/watch?v=MJyUDpm9Kvk

[jamdive]

High aspect ratio wing has less induced drag.

In level flight.... Your trying to use a blanket statement for all conditions and this is incorrect.
The lower the aspect ratio of a wing the higher the angle of attack the wing stalls at.
Higher aspect ratio wings will reverse any benefit if the airfoil is asked to perform at a high angle of attack. Stalling the airfoil induces drag.

The question should be as follows. "What plane holds its energy better under certain maneuvers?"

The best example I can come up with to address both issues would be the f-14. It can change its aspect ratio by simple changing its wingspan. It adjusts its aspect ratio to the best configuration for any type of maneuver.

[bj229r]

I just try to remember which planes jug will catch in zoom--spit is goner..F4...D9...not so much

[FLS]

In level flight.... Your trying to use a blanket statement for all conditions and this is incorrect.
The lower the aspect ratio of a wing the higher the angle of attack the wing stalls at.
Higher aspect ratio wings will reverse any benefit if the airfoil is asked to perform at a high angle of attack. Stalling the airfoil induces drag.

The question should be as follows. "What plane holds its energy better under certain maneuvers?"

The best example I can come up with to address both issues would be the f-14. It can change its aspect ratio by simple changing its wingspan. It adjusts its aspect ratio to the best configuration for any type of maneuver.

Debrody mentioned that pitching up in a Ta152 doesn't bleed energy like a FW190 in reference to his original question about holding vs losing energy.  Why do you think that is? Is it because high aspect wings have less induced drag?

Your point seems to be that a wing has more drag after it stalls. Thank you for explaining that.

Edit: Also Bozon had mentioned leaving something out.