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0 pointsphire3y ago0 comments

Boom were previously targeted a cruising speed of Mach 2.2, I wonder why they lowered it to Mach 1.7 with the latest design update.

Might be related selecting an engine. The previous version of the design had a fantasy engine that didn't exist (I think the specs came from a military engine that they couldn't use due to export restrictions), but now they are working with Rolls-Royce, and appear to have actually selected an engine design. It must be smaller than what they originally wanted, because they moved from a 3 engine design to a 4 engine design.

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galgot3y ago

Supersonic heat also. Concorde was in Aluminum and at 2.1 mach it was at the very limit of what could be done in aluminum. Which required a very "tight" design, engineering marvel in fact. Go faster and one have to go for titanium, which is much more difficult to work with and manufacture.

hinkley3y ago

Didn't the Blackbird weep jet fuel because the seals couldn't hold when the skin was at ambient temperature?

I heard they put enough fuel in it to take off and get up to temperature and then refueled it in the air for safety reasons.

baby3y ago

Export restrictions are not just messing cryptography!

twic3y ago

Maybe military engine control systems work by sending PGP-encrypted emails to the fuel valves?

mrcartmeneses3y ago

But helping mute the airforces of Russia and China

lettergram3y ago

To me that sounds like a fuel saving option. Might extend the routes.

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