News for hackers. Stuff that matters.

A comment on The SR-71 Spy Plane Was So Fast, It Outran Every Missile Fired at It. Parent comment

Re:The SR-71 Spy Plane Was So Fast, It Outran Every Missile ... by justnoise on Wednesday March 27, 2019 @05:08PM (#19506046)
This article summarizes why they refueled after takeoff: https://theaviationgeekclub.com/former-sr-71-driver-explains...

TLDR: They needed full tanks (more or less) or an inert layer of nitrogen over the gas in the tanks before hitting Mach 3 or else the fumes in the tank might ignite. At the end you'll see that they had a system for fueling the tanks on the ground in order to hit mach 3 right after takeoff but it was a maintenance nightmare.

If I remember right, the SR71 could fly at Mach 3 for up to 90 minutes between refuelings. That's significantly longer than any jet ever made.

[ Parent | on HN ]
Re:The SR-71 Spy Plane Was So Fast, It Outran Every Missile ... by sandworm101 on Wednesday March 27, 2019 @05:52PM (#19506466)
>> significantly longer than any jet ever made.

Except the XB-70. Data is rare, but it was to cruise at 3.0 for somewhere between one and two hours.

[ Parent | on HN ]
Re:The SR-71 Spy Plane Was So Fast, It Outran Every Missile ... by briznian on Thursday March 28, 2019 @12:49PM (#19513999)
"Somewhere between one and two hours" sounds a lot like 90 minutes.
[ Parent | on HN ]