how do you get the bleed rates from this graph? also they are in knots per second right?
There isn’t. It has to be done basically from scratch and there is a wide margin of error considering the nature of the sources.
The Harrier tactics manual may or may not be using 17,211lbs as the reference weight for the paragraph about 19 degrees per second. For instance the engine diagram for thrust he likes to use is uses “Standard Weight” of 15,500lbs which is basically clean and 50% fuel. The other issue is that the CL/CD diagrams posted do not show a Mach number and even that difference is appreciable. The reference diagram is also likely for a clean airplane. Lastly it is unclear whether or not the engine diagram is utilizing installed thrust values or uninstalled thrust values.
Adding all of those factors in would significantly degrade the performance of the plane.
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284 knots per second is egregious, is that a high estimate for bleed rate?
The estimates are in feet per second.
But also keep in mind that the CL/CD diagrams have a wide variation depending on who is doing them and what speed they are done at. For instance the CL/CD diagrams Matrix posted appear to be from this study.
He doesn’t say that because once again it is stringing a bunch of different sources together and attempting to cherry pick. For instance the CL/CD diagrams in here are probably at very low mach number which will skew results.
It should also be noted that study seems to be centered around basically very low speed flight / landing the aircraft. There are other CL/CD diagrams contained that at least appear to make the plane appear much worse in CL/CD when the thrust is vectored. At least that is the way it reads at a very quick glance.
This is NASA CL diagram for Harrier. You can get a sense how sampling at different mach numbers will skew the data. Using Mach .1 data in place of Mach .5 data will skew the estimate and skew it to be more favorable than reality.
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HAHA
You didn’t even read that source BTW
That chart you just posted was the computer analysis were all values were normalized between 0 and 1
They did that to make it easier for the computer to simulate.
The chart you posted was not the real values….
So well done, you failed to fully read the document and now you are posting FALSE information
The maximum lift coefficient in that document is actually close to 1.5
However they took the values and then normalized them meaning that 1 is now equal to about 1.5
So the AV-8B is actually achieving a lift coefficient almost as high as the flanker for just a -.147 drag coefficient
Do you think CL values change with speed? Yes or no?
Slightly
That doesn’t change the fact that you used the wrong number entirely mkay
What number did I use and where did I use it?
You posted the un-trimmed lift coefficient and you assumed that was the actual lift coefficient
But you failed to read (N.D) next to it meaning normalized
You’re numbers are going to be about .5 off
No I did not. Go back and read.
No you did,
You said this is a CL diagram for the harrier
THAT IS FALSE INFORMATION
That is nearly the 0-1 normalized data of the real lift coefficient
(note the (N.D)) Normalized
Yes and? It is used as an example of showing how CL is different even at subsonic mach numbers.
What makes you think that these estimates are off and by what margin?
Ok are you failing to realize that the numbers are a good .5 off their maximum?
And again that’s for a harrier 2 anyways so why are you applying it to the harrier 1?
Also what did you calculate net thrust on?
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This chart is based on what exactly now
Seems like you pulled it from thin air
It’s based on math. The numbers represent calculated negative SEP at 18 degrees for 60 degree nozzle deflection or 15 degree nozzle deflection.
Now answer the question.
It’s really not and to answer your question from earlier
Even the FA.2 weighs 13,000 - 13,500 lbs operationally dry
The AV-8B NA is at 16,500 dry
Lmao
So tell me how can the harrier at those bleed rates
Perform 90 degrees of turn and only lose 100 knots