On July 24, its new light sport rules took effect under MOSAIC, built around a new certification part, Part 22. Gone is the weight cap that boxed in light sport aircraft for twenty years. In its place is a performance based rule that gates the category on a 61 knot stall speed, and that allows electric propulsion and, in the FAA's own words, any number of engines.
Dassault Aviation just pushed the 10X into service to the second half of 2029, blaming the tighter certification rules that followed the 737 MAX. The aircraft features a bunch of innovation taken from their Rafale fighter jet.
At altitude you can reject heat straight to the aircraft skin. Some designs run an internal heat sink on the ground and during climb, watch altitude, and only switch on the skin-exchanger coolant pump once outside is cold enough to cool the loop for free.
The reason it stays a refrigeration unit and not just vents is the ground case. Gate on a hot day, doors open, no ram air, warm soak: that's the worst case, and where the compressor has to work. One published point-of-use chiller design specs roughly double the load on the ground vs in cruise (order of 700 W vs 300 to 400 W per unit). So the vapor cycle is sized for the ground, and most of a 20 hour flight is spent in the regime where you barely need it.
And these aren't fridge boxes at each cart. It's a central vapor-cycle chiller cooling a glycol/water loop piped to air chillers at the galleys; the carts get chilled air. The heat comes off the condenser and goes to ram air, a skin exchanger, the cargo hold, or back into the ECS, depending on the aircraft. Which one the new ULR units use, Airbus hasn't said. For a 22 hour flight the interesting number isn't peak capacity, it's efficiency and weight in cruise, which is probably what "lighter and more efficient for very long flights" is pointing at.
Was once on a flight sitting at a gate with a faulty ground air connection or something, and they weren't allowed to run the APU at the gate due to pollution. It must've been 40 degrees (Celsius) inside, at Singapore Changi, and they were delayed at the gate too. Everyone breathed a sigh of relief when we started moving and got air conditioning from the engines.
Thanks for the research. I guess they've been talking about it for a while and will probably continue to do so. Aviation innovation always moves slowly and it's usually a good thing. Which means marketing departments keep writing the same press releases.
I guess we'll see after the tests.. but, it looks a bit dangerous, perhaps. A prop may also save (fuel, not time) but they're rarely a good choice for an airline (unless short-haul and the airport/taxi time counts as the majority of "flight time")
1/ If a blade snaps on a normal engine, the metal casing catches it. With an open fan, that broken blade turns into shrapnel flying straight toward the passengers, fuel tanks, etc.
2/ The blades would be huge. You can’t just hang them under the wing of a normal Boeing 737 or Airbus A320.
3/ The metal casing on a normal engine acts like a giant muffler. Open rotors are loud.
4/ Open blades have no protection from bird strikes, hailstorms, or runway debris.
My read is that they're announcing a plan to build non-folding wings to test the geometry they would eventually want with folding wings. Which makes sense but isn't very exciting.
It's not just geometry, it's also where the mass is. And the rigid areas.
Aircraft wings oscillate during flight, the location (and movement) of mass within them (e.g. fuel) is critical to model.
Also, the location of the fold is likely less flexible (e.g. more rigid) than the remainder of the wing. This will greatly affect the dihedral angle of the remaining outboard portion of the wing.
