The Mach 1 (speed of sound) at FL350 in ISA conditions is 576.6 kt, above FL361 Mach 1 is 573.8 (up to about FL850).
Normal cruise for todays jets is around M0.82, in the FL350-FL400 region.
- FL350 M0.82 = 473 KTAS (353 KEAS)
- FL400 M0.82 = 471 KTAS (331 KEAS)
Sonic cruiser (#1), design cruise at FL400-FL450 M0.95
- FL400 M0.95 = 545 KTAS (384 KEAS)
- FL450 M0.95 = 545 KTAS (362 KEAS)
Sonic cuiser (#1) is 15% faster at FL400 than a current jet at FL350, 16% faster than a current jet at FL400.
Sonic cuiser (#1) is 15% faster at FL450 than a current jet at FL350, 16% faster than a current jet at FL400.
Sonic cuiser (#2) design cruise at FL400-FL450 M1.2
- FL400 M1.2 = 689 KTAS (485 KEAS)
- FL450 M1.2 = 689 KTAS (457 KEAS)
Sonic cuiser (#2) is 46% faster at FL400 than a current jet at FL350, 46% faster than a current jet at FL400.
Sonic cuiser (#2) is 46% faster at FL450 than a current jet at FL350, 46% faster than a current jet at FL400.
Edit : thanks babble silly mistake the numbers didn't even look close !
[This message has been edited by Zeke (edited 15 May 2001).]