To be fair, above FL400 4̶0̶A̶G̶L̶ is relatively high for most airliners. Most are between FL300 and FL400.

FL400. 40 AGL is doable for almost all airliners ;)

	▲	lisper a day ago \| parent \| next [-]
		Actually that would be quite challenging over most terrain.
	▲	aschla a day ago \| parent \| prev \| next [-]
		Thanks. Meant to slap a k on that 40.
	▲	sire-vc a day ago \| parent \| prev [-]
		Almost all? Now I'm interested