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Old 08-08-2012, 12:34 AM
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Crumpp Crumpp is offline
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Who said anything about infinite acceleration?

Quote:
....if you are throttle closed then there is no thrust vector
Did they teach you this in your flight training? I highly doubt it.

Wow, guy....

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lift opposes weight and thrust opposes drag,
Only in level flight...

Check out a climb triangle, pilot. A dive is the same as a climb, only difference is how we sum the force vectors.

Weight changes at the sine of the angle.

Sine 90 = 1

When you point the nose straight down (90 degrees), all the weight becomes thrust.

So even though you pull back the throttles on your 2000 hp WWII fighter that weighs 7000 lbs....

Let's see...

Sine 90 * 7000lbs = 7000 lbs of thrust going straight down!

Compare that too:

2000hp*.8np = 1600thp

Thrust @ 150 mph = (1600thp*325)/130.35Kts = 3989.26lbs of thrust.

So you instead of the 4000lbs of thrust available from your engine at full throttle, you have only added almost twice as much at 7000lbs!!


Quote:
lift actually adds to drag because lift generates induced drag, if you fly at 'zero lift' then there is no induced drag.
The lift vector is now shifted 90 degrees. The wing still generates lift but it is only opposed by drag. (Weight cosine 90 = ZERO)

The plane will not fly straight down unless held at the zero lift angle of attack. Instead, lift will accelerate it on x-axis or what you know as the Thrust and Drag axis from level flight.

Yes there is induced drag too.


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since when did lift oppose drag?,
In a verticle dive.

All this is off topic, take it somewhere else.

Start a new thread if you want to understand the forces of flight.

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Actually Crumpp I think you might find that in EVERY current front line fighter deliberate spinning is prohibited !
Most fly by wire systems are set up to act as antispin devices. It does happen on accident though. It is generally not recommended for training because of the relaxed stability of most Fly by Wire fighters.

Sort of like the longitudinal instability of the Spitfire...only much more extreme.

Quote:
As for spin training that should imo be mandatory as well ... sadly however it has been removed from the basic syllabus in a lot of countries.
Absolutely. It was a requirement for my CFI. Accelerated stalls are back too for Commercial certs. I was glad to see that.
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Last edited by Crumpp; 08-08-2012 at 12:50 AM.