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na85
11-20-2007, 12:57 AM
Could someone please clarify the difference?

AFAIK, best climb speed is the speed at which altitude increases the fastest in a sustained climb.

Vertical maneuvering speed, though, I'm not so sure about.

Is there a resource somewhere for determining these speeds for different aircraft?

na85
11-20-2007, 12:57 AM
Could someone please clarify the difference?

AFAIK, best climb speed is the speed at which altitude increases the fastest in a sustained climb.

Vertical maneuvering speed, though, I'm not so sure about.

Is there a resource somewhere for determining these speeds for different aircraft?

K_Freddie
11-20-2007, 02:40 AM
Best climb speed it usually documented with a/c specs somewhere. As for vertical maneuvering speed, don't bother. Combat is not by the book, but by the seat of your pants. Doing it bookwise, gets you a hole in the ground
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na85
11-20-2007, 02:26 PM
But what is the definition of vertical maneuvering speed?

Speed required to do a loop? An immelmann?

BlitzPig_DDT
11-20-2007, 02:47 PM
Na, there are too many variables. Like K_Freddie said, you can't really fly with one hand on the stick and the other holding the manual.

For example, you may need X amount of speed to do a loop, and it may also be the best for ease of doing it (pilot work load), but if the enemy is moving faster than you, you are too slow. Likewise, when talking about a loop or an immelman, you have the same issues you have in a flat turn - tightest physical circle, or fastest time through, and then instantaneous rate vs sustained rate, etc, etc.

Think of it in more general terms. If you are in a heavier fighter (US, or LW generally), keep your speed as high as possible, and maintain gentle movements. Approach it like chess, and try to be several moves ahead of your opponent so you don't have to maneuver hard and blow your speed. If you are in light planes (Japanese, Soviet, etc), then keep the speed down. They don't like to dive fast and will break up, they also often lose control authority at high speeds, and you approach the point where the pilot is the limitation, and THAT is the same for all planes. In the ligher planes you want to stay slower, where you are much more agile, and side step their attacks and try to drag them down to your speed and control the fight.

JG14_Josf
11-20-2007, 03:14 PM
na85,

Vertical Maneuvering Speed is a term utilized in Fighter Combat (http://www.amazon.com/Fighter-Combat-Maneuvering-Robert-Shaw/dp/0870210599) by Robert Shaw:.

http://ecx.images-amazon.com/images/I/513P2687GSL._BO2,204,203,200_PIlitb-dp-500-arrow,TopRight,45,-64_OU01_AA240_SH20_.jpg

The term designates the minimum speed in level flight required to perform a vertical up maneuver such as the pitch back after the Sustained Turn Technique is employed.

In context the term is used as the higher speed between corner speed and vertical maneuvering speed. In other words; when setting up a pitch back during the Sustained Turn Technique the pilot maintains corner speed or vertical maneuvering speed (whichever is higher) while performing a nose to tail turn after the merge.

Naturally; if corner speed is higher than vertical maneuvering speed, then, there will be enough energy to perform the pitch back after the second merge, where, the attacking pilot pitches straight up and then pitches back over the stalled out target that cannot follow because it burned too much speed in the Sustained Turn while going for angles.

If corner speed is lower than vertical maneuvering speed, then, maintaining corner speed during the sustained turn will not be sufficient to perform the vertical maneuver after the second merge.

Does that make sense?

na85
11-20-2007, 04:59 PM
Yeah that makes sense. Kind of a vague definition, though.

BSS_Sniper
11-20-2007, 05:44 PM
As far as best climb speeds, there are more than one. There's Vy, Vx, Vyse, Vxse and a lot more V speeds that are committed to memory for each aircraft you fly. Vy is best rate and Vx is best angle. The se is for single engine performance on twin's. Just FYI.

Interesting to note, and I could very well be wrong, but it doesn't seem like Maneuvering Speed (Va) is incorporated into the sim. For those that do not know, that is the speed at which if you are above and use full and/or abrupt deflection of the control surfaces you will cause structural damage. Also could damage the aircraft in turburlence.

11-20-2007, 08:40 PM
as a general guide for you, think of your minimum verticle man speed as the lowest speed you can reliably get your bird to loop without a stall. this is a good number to keep in your head during combat in any craft. doors begin closing under that number even tho you still have vert options. this has always helped me. I second Josf, read Shaw.

na85
11-20-2007, 09:04 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by MOH_MADMAN:
as a general guide for you, think of your minimum verticle man speed as the lowest speed you can reliably get your bird to loop without a stall. </div></BLOCKQUOTE>

Are these numbers published anywhere?

JG14_Josf
11-20-2007, 10:13 PM
Corner Speed is Va (http://flighttest.navair.navy.mil/unrestricted/FTM108/c6.pdf)

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Beginning at zero airspeed, two curves diverge to describe the maximum lift
boundaries for positive and negative load factors. Since the lines represent stall, operations to the left of these curves are beyond the capability of the airplane, except in dynamic, unsteady maneuvers such as zoom climbs. From the example shown, steady flight is not attainable below 100 kn, the 1 g stall speed. At 200 kn, 4 g is attainable, and so on, with increasing load factor capability as speed is increased. At some speed, the load factor available is equal to the load limit of the airframe, nL. This speed is called the corner speed or maneuvering speed, VA. The significance of VA is developed in later sections. The same constraints define the negative load factor capabilities and negative g corner speed. Notice the negative g available at any particular speed is typically lower than the positive g available, due to the wing camber and control power effects. The envelope is bounded on the right for all load factors by the limit airspeed, VL. </div></BLOCKQUOTE>

Corner Speed is extensively documented for Fighter Planes. Here is where T/W becomes a significant factor. If the aircraft has more T than W, then, vertical maneuvering speed is what?

As vague as it may seem in theory the actual practice of vertical maneuvering speed is either enough or not enough; not vague.