OK (another day) ... let's start with an appeal for current information. What's available (which manufacturers) in terms of:-
1) Trolleys (suitable for transport incubators)
2) Transport incubators themselves
3) Ventilators (suitable for transport incubators)
Big Tony (
aka the Vanquished One) has reminded me that for "heroic" transport journeys (
eg, long distances by air), the limiting factor (or, at least, one that needs careful logistics) is the number of oxygen cylinders likely to be needed. That, and the capabilities of the accompanying staff in changing them!

Meanwhile, here are a few links to ponder:-
AtomAirborneCobamsDrägerFernoLMENice NeotechPhoenixOr ... how about thinking outside the
box (literally)? And (lastly), what about some
history?
Actually (as any keen researcher will no doubt discover), there is a
ton of stuff about this topic out there on the web. I have noticed some terminology that crops up now and then, and it reminds me that we need to be a bit more specific about what is meant by "transport incubator" (that is, there are sub-categories, depending upon intended use). For example:-
1) "Intra-hospital" - wheeling the neonate from place to place within the hospital (the G.E. Airborne
750i is pitched at this level, apparently), untethered, whilst being ventilated, and all the rest.
2) "High-dependency" - the sort of transport we are talking about (that is,
outside the hospital, and generally by road vehicle or aircraft) - the
Globe-Trotter, for example.