"Paul J. Adam" wrote:
:In message , Fred J. McCall
writes
wrote:
::What makes you so certain that gunnery radar WILL lock on to a stealthy
::UAV?
:
:What makes you think that fighter aircraft use gunnery radar?
:
:The pilots say so.
snip
:Sounds like the gunsight uses radar, Fred.
Yes, I know, Paul. I work with pilots all the time. But it doesn't
HAVE to, the way the respondent was trying to insist that you HAD to
get a lock or you couldn't shoot.
snip
::The UAVs are designed, after all, to avoid being picked up by
::radar. For defence planning purposes the assumption has to be that
::radar will not probably work against them, unless and until it is
:
roved to be capable of doing so. To take any other attitude would be
::foolish complacency.
:
:Which means nothing, since a fighter attacking with a gun uses
:EYEBALLS to get the target and they're way up close.
:
:And then the gunnery system uses RADAR to get the range input, and after
:a few seconds adds velocity, and after that accelerations, to take the
:gunsight from Level III (locked on, range available) to Level IV (full
:system functionality)
But you can still do it better than the "WWII" accuracy claimed, even
if you're pure visual. There are tics on the HUD that you can stick
the guy between if you have a rough idea of his size and you can get
the approximate range that way.
:The range becomes particularly significant when you're shooting at a
:target only a foot in diameter (like a ScanEagle seen from behind) - but
:your ammunition drops more than twenty feet over a thousand yards.
With something that small you'd be a lot closer. If you didn't
realize what it was you'd probably miss on the first pass (you'd be a
lot closer than you thought you were and would shoot over him).
::Hint #2: unlike the Luftwaffe's ammo, the current standard US 20mm
::aircraft SAPHEI shell, the PGU-28/B, does not have a tracer - so the
:
ilot will have no idea where his shots are going.
:
:Nor does he need to. It's NICE to have radar, but it's hardly
:necessary in order to score a lot of hits with a modern gun and HUD.
:
epends on the size of the target and how long you have to shoot at it,
:doesn't it?
It's a slow UAV. Where's it going to go other than down, Paul? You
have all the time in the world to shoot it.
::How, exactly? Ordinary MGs with eyeball sights stand hardly any chance
:
f connecting with a small plane at an unknown distance and travelling
::at an unknown speed, unless it comes very low and close. Radar FCS
::would probably not even pick it up.
:
:And none of that applies to most modern aircraft, or even most modern
:air defense weapons in general.
:
:Unfortunately we're not talking "most modern aircraft" when discussing
:such small targets.
Really? What do you think a CVBG is going to send out after them?
Butterfly nets?
:Assume the radar locks on, or that Dick Dastardly in the fighter is such
:an expert marksman he can hit by eye every time. A ScanEagle UAV is
:about a foot in diameter, seen from astern: a F-16's gun puts 80% of its
:rounds in a six-mil circle. At 1,500 feet, the target occupies only 1%
f that circle.
And you'd probably check fire until you got closer. It's not like it
can run away.
:Mathematically, if you fired an 86-round burst you would have a 50%
:chance of hitting it. To get the chance of a hit up to 95% takes you to
:a burst of 372 rounds, still assuming that the target remains in the
:six-mil circle throughout...
You're leaving out a factor. The rounds are not evenly distributed
through that six mil circle. They're still concentrated toward the
center. You need to work it as a Gaussian rather than a random spray
throughout the circle.
:This is the best case, assuming the burst is perfectly aimed throughout.
:Any errors - such as misjudging range because of a lack of radar lock -
:will make things worse.
Actually, it would probably make things better after the first pass,
since you'd be a lot closer. Probably miss with the first pass (shoot
over it judging by the visual range cues in the HUD because you'd
overestimate the range due to the small size) and get it with the
second pass.
Hell, fly close enough to it and it'd probably crash on its own just
from the turbulence.
--
"May God have mercy upon my enemies; they will need it."
-- General George S Patton, Jr.