Re:United Airlines will buy 15 planes from Boom Supersonic
by V_Terranova_Jr on Thursday June 03, 2021 @03:23PM
(#27386119)
The sweet spot for civil supersonics from an aircraft design standpoint is less than Mach 2. You can maintain good propulsion system performance without variable geometry inlets, boom strengths are lower, aeroheating loads are lower, fuel burn is lower, etc. Operating expenses will be significantly lower for such an aircraft. Maybe Boom is finally realizing the importance of all this as well.
Whether that's enough travel time reduction to make these aircraft worthwhile is definitely a valid question. The low-boom technology that NASA is pursuing is for sub-Mach 2 aircraft (I don't believe Boom is pursuing a low-boom design, but I haven't followed closely as I don't consider them a credible organization either).
Re:United Airlines will buy 15 planes from Boom Supersonic
by dannyw on Thursday June 03, 2021 @12:52PM
(#27384073)
A halving in speed sound amazing!
Re:United Airlines will buy 15 planes from Boom Supersonic
by SamBam on Thursday June 03, 2021 @02:10PM
(#27385168)
Even if we say doubling instead of halving, I assume that the total portion of a transatlantic flight that it could travel at top speed would be pretty small, so the total time might still be more than half.
Re:United Airlines will buy 15 planes from Boom Supersonic
by nopzor on Thursday June 03, 2021 @06:01PM
(#27387976)
other than lower speeds during approach and departure around controlled airspace with speed restrictions, the overwhelming majority of a transatlantic flight will be at full speed.
of course, there are exceptions with congestion, hold patterns, excessive vectoring, etc, but this is generally true.
another thing to keep in mind is headwinds/jetstream. when going west across the atlantic; they can often be 100+mph. so the delta between boom and eg. a 787 becomes even more pronounced in this situation.
Re:United Airlines will buy 15 planes from Boom Supersonic
by t0mas88 on Friday June 04, 2021 @02:56AM
(#27391301)
Typical height of the polar front jet stream is 30-40,000ft, that's great for a 787 that's most efficient exactly in that altitude range. But doing mach 1.7+ you want to be much higher for efficiency, so it's entirely likely that the Boom plane will miss the jet stream.
Re:United Airlines will buy 15 planes from Boom Supersonic
by Dylan16807 on Saturday June 05, 2021 @01:09PM
(#27406761)
They're talking about going against the jetstream, so that doubling air velocity means more than doubling ground velocity. If the boom plane gets to miss the jet stream entirely that only improves the situation.
FYI, most airliners already fly at or above 0.85 Mach. 1.7 is faster than 0.85 but operationally it will only be only an incremental decrease in total travel time.