(Jim C) wrote in message . com...
(Mike Miller) wrote in message . com...
(Jim C) wrote in message . com...
Did anyone notice that the high altitude nozzle extension seems
to be attached when first fired but does not seem to be there
later? The picks at scaled.com show the large black extension
at first but after burnout it is gone (2nd powered flight). The best
view of it is during the cold flow test during an earlier flight.
It also seems that the first powered flight didn't use it at all.

Since Spaceship One isn't exactly operating at its planned-for "high
altitudes," they probably removed the extended nozzle to study other
aspects of the engine's performance before adding the complication of
the new nozzle.

Mike Miller, Materials Engineer

Actually, both of the powered flights have started at the planned-for
high altitudes. I believe the extention is sized to the release altitude of
about 50K feet. If you have looked at the pictures at scaled.com, you may
have noticed that the second flight starts with the extention attached and
ends with it missing. Does anyone here know Burt and can ask what's going on?
How about Jeff G? You're a rocket guy...Assuming you still read these groups.

It would make sense to have a disposable outer nozzle to shape the
thrust at release alitude. Their is a significant pressure difference
between 50,000ft and 62 miles.

What happens to this outer segment? Does it burn up or is it
jetissoned?

Josh

Jim C.