My husband and I were just looking at some info about the SR71 Blackbird...?

Question

It said the pilots were fed only a "high protein, low residue" diet before flights..what exactly does that mean, and why? Was it to prevent excess cleanup after mach3+ pressure, or to keep them alert?

Answer 1

First, there is no Mach 3+ pressure. There is no stress on the body at all. Much like sitting in an easy chair and having the scenery pulled toward and under you. At high (60000+ ft) even the world seems to move slowly. Secondly, the Blackbird driver routinely got a flight physical before each flight. Prior to the examination, he would purge his lower digestive tract with laxatives. Then the diet of high protein, low bulk was available. A typical meal would be lean beefsteak, eggs, fruit or fruit juice, wheat roll, butter and jam. Baked fish, roast pork can be substituted or added for the entree. Veggies and breads varied. As far as staying alert, there are systems to monitor, fuel management in flight to keep the center of gravity and center of lift from misbehaving, radio traffic with the home 'drome, in flight refueling, etc. Yes, it is boring overall. If anyone ever made a realistic movie of the routine, no one would pay to see it.

Answer 2

Even though the flight s were extremely fast in plane speed .
some say as fast as mach 4 , they were sometimes still very long flights , so high protein was great for keeping them alert
and low residue help them from having to defecate

Answer 3

Maybe a little bit of both. The blackbird is an amazing aircraft. It should have never been declassified.

Answer 4

Their flights lasted hours and hours, there was no restroom but the suit, and the protein provided long term energy and mood stabilization.

Answer 5

It was so they did not have to defecate on long missions. Most of the SR-71 missions were long in time and travel.

Answer 6

Yep no wanting to poop in your clothes.