Not really. I just don’t like seeing misinformation being spread hence me pulling you up on the AMRAAM body lift issue.
Do you even understand what you write? The quote in your article is this:
The missile is much faster than its
predecessor—about Mach 4 according to
some estimates—and there is more body
lift at higher speed.
The formula is 
where p= air density, v = airspeed, A = lift surface/wing area, CL = lift coefficient.
At mach 4 with an alpha above 0 you will get some extra lift, but not much. Most will still come from the wings. And to be fair, at mach 4 even a wooden plank would produce more lift than a static or slower one. But it’s not built with a lifting body and the tiny amount of body lift is negligible.
At Mach4 Cl is huge (as is Cd).
Missiles hve very small fins (lifting surfaces) simply as they are fast: they don’t need that much surfaces to generate the necessary lift and then can keep drag low.
As I hve alrdy says on other forum, you can’t compare apples and oranges: W/S reasoning is completely irrelevant if you are not dealing with similar configurations.
In your formula you simply hve discarded the most weighted factor. Orherwise it’s a good read.
Well, I simply used the most relevant numbers. The max turn rate is around 40-45G and the thrust is likely 40-60G. So it is easy to assume most lift will come from the thrust.
If you, for instance, look at how CL is calculated you will see that it is based on a division by airspeed. And If you look at turn envelopes you will see a similar result. As yourself why it is that the F4 only can reach lower and lower G:s the faster it flies and how this effects a missiles agility when it has no excess power.
I wonder if SAM designers would agree with your hypothesis. I have seen some pretty effective manoevring well after motor burnout.
I posted a pretty good read on the topic.
Part 6.12 is a good start.
http://www.aviation.org.uk/docs/flighttest.navair.navy.milunrestricted-FTM108/c6.pdf
I have put it all together (the formula for calculating the turn performance along with a description of how they all work togehter).
I would say that its more than a hypothesis. Max thrust is usually 40-60G, I don’t know exactly what it is for the AMRAAM.
So after burnout you wont see much turn performance. Im sorry.
EDIT: What you might have seen is a smokeless sustainer. Little thrust but enough to let it have some agility left. Or they have had better control surfaces. To be able to turn you need lift (larger wings provide more lift). But then again, all is relative. A modern jet with a t/w ratio in excess of 1 with a wing loading of 350kg/m2 will always out turn a flying body with no thrust and a wing loading of 2’200 – 4’400 kg/m².
EDIT 2: I may of course be wrong, but if I am please point out where the error is. So far it feels like it follows logic pretty well.
no what i mean is if you have 2 perpendicular surface it will result in very high rcs , even if enemy come only a few degree from front that why most stealth fighter have v tail
There are two effects in play, one is the direct reflection and the other is the corner effect. You will still need to come in pretty much from the 90 degree abgle to make use of both but we can stick to 88-92 degrees if it makes you happy 🙂
Here are the charts of the RCS:
A perfect reflector on a normal ac is a perpendicular 90 degree corner, its the same principle as the radar reflectors yachts and/or decoys have.
depend on how modern the AESA is ,and algorithm
Always. Thats why the libraries and software continously get updates and need the updates.
i know what you mean but my point is that a small burn out missiles will be quite hard to detect , so may be the time pilot detect it they dont have enough time to maneuver , and yes missiles will lose speed by maneuver but they also gain some speed as they diving down , remember :eagerness: , btw we dont know the nez of aim-120 and meteor yet , why you assume they are 10 km and 30 km ???? , i think it much more at least for the case of meteor since it is ramjet the NEZ could be 60-70 km , about the high PK , i dont think you need very high pk even if the the pk is very low like 40 % then 2-3 missiles pretty much shot down target , it not an action movie so we dont need 1 f-35 to shot down 100 enemy aircraft right ?
Ok, I will explain it as good as I can.
To make sharp turns you need a combination of lift (derived from wing geometry and speed) as well as thrust.
A modern missile, like the AIM120D, has a wing loading of 2200kg/sqm and the jets have 250-350 kg/sqm + lifting body (usually).
This means a missile needs higher alpha (exponentially growing drag) which has to be countered by more thrust (otherwise it loses its speed and stalls).
So the turn capability of the missile is depending on thrust, or more specifically the combination of lift (from high alpha) and thrust lift where the control surfaces account for a very small part of the actual lift (as in the wings by themselves don’t do enough, they require lots of thrust to be effective). You also should remember that at mach 4 you need lower turn rate (deg/sec) to get high G.
When you remove thrust you basically have the least menuverable object in the sky. A modern MAWS will detect the missile before flame out and it will be hot enough to be spotted afterwards as well (but with shorter notice).
So thats why I only count the propelled part of the envelope as high Pk envelope and the area where you would want to engage enemies within. There are a few exceptions historically but generally this is how it looks.
More to read here: http://www.aviation.org.uk/docs/flighttest.navair.navy.milunrestricted-FTM108/c6.pdf
yeah and triangulation have very big problem gain low side lobe radar like an AESA :eagerness:
As long as you have to directional beams that intersect you can position a target.
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