How fast could the SR-71 go?

Question

The book says a design speed of Mach 3.2 and a max useable speed of Mach 3.3. (1925 KTAS)

In order to maintain combustion, the airflow has to be slowed down to subsonic (actually, about 800 feet per second). This causes high inlet temperatures which are limited to 427C.

Given that the energy in the airflow is equal to 1/2 density times velocity squared, any increase in the speed of the SR-71 would cause the temperature to rise exponentially. (At least that's the way I understand it)

So how much faster could it really go since it was at the limits of technology in the 1960s?

J.B.1972, where did you get that info from? 3.7 is very fast!!!

Answer 1

think about this first... a normal boeing flies at about 580 knots at about 35,000 feet... during the summer the outside air temperature can reach -50* F. From 600 to 900+ degrees Fahrenheit on the airframe. Temperatures on the J-58 engine exhaust reach 3200 degrees.
the SR-71 has been publicly recorded to fly at about 3.3 or 33 miles a minute, but can definately be pushed to go faster, however that ofcourse is classified, it is capable of traveling in the mesoshpere.

Answer 2

The SR-71 Blackbird was built as a reconasense plane to fly over the Soviet Union, during the cold war. It's speeds were unusally fast, well at the time they were. The SR-71 is no longer in active use. To my knowledge it could move fast enough before being shot down depending on the enemies missile technology. If it was a country with much money to spend on military advances then I'd say no, but if not the plane would be able to fly over a country in short amount of time with out being brought down. There was once a Stealth Bomber shot down over the Middle East, so you just never can tell.

Answer 3

The true top speed of the SR-71 is still classified to this day.

The engine design of the SR-71 is such that at the highest speeds and altitudes it functions as a ramjet, not a turbojet. Note the moveable cone in the front of the engine.

Answer 4

It's top speed is Mach 3.3+
It can go from Los Angeles, California to New York,New York in less than 30 minutes(you can't find that information on the internet one of my old teachers told me that)
and calnickel u give way to much infornmation

Answer 5

There are many references to the top speed of the SR-71, but none of them are correct. The top speeds you see are only the ones reported. Maximum altitude and speed are still classified.
When they were decommissioned a few years back, one went from LAX to Washington National in 64 minutes. It took off from Edwards AFB, went over the Pacific to fuel up, passed over LAX and started timing. This aircraft is on display at the Udvar-Hazy Center in the Smithsonian.

Answer 6

Officially it went Mach 3.302 when it established the sustained altittude and velocity records.

It probably went faster unofficially, but any numbers would be classified. Guess would be Mach 3.5, but then, who knows?

Answer 7

hmmm

from what i understand, it wasn't the engines that were the weak point of the aircraft in limiting its speed to mach 3.3..it was that little strip of titanium in the front window.

oh you might be able to burst the speeds up temporally higher...but that little piece of titanium would actually get soft and threaten to blow out at high sustained speeds.

Answer 8

Mach 3.5 (2,500 mph)

Answer 9

3.7 ( april 8th 1968)