On Fri, 20 Aug 2004 01:31:17 -0400, Venik wrote:

Vello Kala wrote:

Aircraft Speed Altitude Mach Number
SR-71 Blackbird 2,275 mph
(3,660 km/h) 80,000 ft
(24,385 m) Mach 3.35
MiG-25 2,110 mph
(3,390 km/h) 42,650 ft
(13,000 m) Mach 3.2


This data is from Aerospaceweb. Question: SR-71 looks like alien plane, have
very special design (incl tanks what start to keep fuel on flight only)etc
etc. Mig-25 looks as pretty usual plane. But difference in speeds is
relative minor, expecially if to look at what altitude it is reached. How it
is possible? Do anybody have more data? Say, about SR-71 performance at 40
000 feet?


I don't think that comparing MiG-25 to SR-71 is entirely inappropriate,
considering that the Blackbird was one of MiG-25's primary targets and
both aircraft were designed for high-speed, high-altitude recon roles.
MiG-25 was designed as an interceptor and in this role it has
outstanding performance. MiG-25 can be compared to SR-71 in terms of
performance needed to intercept the Blackbird. MiG-25 certainly had the
right performance for that. MiG-25 was also designed as a recon plane
and in this role it can also be directly compared to the SR-71.

And some comments about the comments in this thread. MiG-25 is not made
of stainless steel but of nickel steel alloy similar in composition to
the nickel alloy used for X-15. The Valkyrie, on the other hand, was
made of predominantly stainless steel.

Operational requirements for MiG-25 differed drastically from those of
SR-71. MiG-25 was designed to operate as any other Soviet fighter
aircraft without any specialized facilities. This was also a factor in
the choice of airframe design and construction materials. Nickel steel
alloy used in MiG-25 construction does not carry a strength penalty when
compared to titanium. MiG-25 was build to have an exceptionally strong
airframe. One must not forget that MiG-25 had to meet a substantially
higher level of airframe stress requirements than SR-71.

MiG-25 was a mass-produced combat aircraft (a total of 1,186 were
manufactured), while the total production run of the entire
A-12/YF-12/SR-71 line was only 49 aircraft or so.

And this would explain the fact that the Mig-25 never managed to intercept
an SR how? The Mig simply could not catch an SR-71, and probably
could not even track it. The SR-71 succeeded, the Mig failed.

Al Minyard