[Prev][Next][Index][Thread]
RE: (meteorobs) Fwd: Meteorite said to start backyard fire
GeoZay wrote:
>
>
> In a message dated 12/7/00 12:44:34 PM Pacific Standard Time,
> terry.johnson@rcenter.org writes:
>
> <<
> GeoZay and all, the SR-71 and other supersonic jets do have
> to deal with
> frictional heating. In fact, the SR-71 is limited in
> velocity BECAUSE of
> the heating of the wings, windshield, tail, etc. Pilots do
> not fly it over
> 2100 MPH except in certain conditions, but it could
> theoretically go over
> 4100 MPH if heat and vibrations were not a factor. When
> authorized by the
> Commander, crews are allowed to go over Mach 3.2 if the skin
> temperature
> does not exceed 427 degrees C. In fact, to properly track
> an SR-71, you
> wouldn't use radar, you'd use infrared detectors. >>
>
> I don't doubt these aircraft get quite hot while in
> supersonic flight. How
> hot is it by the time it lands, after the outer parts have
> been air cooled
> prior to landing at slower speeds? I don't think these
> aircraft are designed
> to absorb heat, but rather to re-radiate it back to the air
> at a fairly quick
> pace.
> GeoZay
Not my point. My point was that speeds of only 2000 MPH can cause
considerable heating. At what point above the ground will a meteor fall
below the 'heating speed'? (I'll bet they don't want the aircraft dropping
from the sky quite as fast as a meteorite) :o)
If the meteor will absorb frictional heat for velocities over 1500 MPH (<--
I'm just guessing a number blindly here), how long will it fall after it
slows under that speed? The cool-down time will only last for as long as it
takes to fall that last bit. Whether that time is measured in minutes or
seconds will determine the temperature upon landing.
Now, who has done the calculations? C'mon, speak up! Anyone work with the
airforce calculating air density gradients or frictional heating??? We're
all waiting for your answer Mr. Beuhler! :o)
--Terry
www.rcenter.org
To UNSUBSCRIBE from the 'meteorobs' email list, use the Web form at:
http://www.tiacdot net/users/lewkaren/meteorobs/subscribe.html
References: