The noise that they do make is carried away with the wind. The occupants share the fuselage with the engine in the single-engine variants, but the engines on the V-Twin ride out on the wings, outside, and behind, the cabin. The result is an airplane with much more pleasant handling than the single-engine stablemates.Īlso remarkable in the V-twin was the absence of noise. The central-mounted vertical stabilizer on the V-Twin is sized to accommodate up to 230-hp engines, so the airplane is very stable in yaw, and the rudder response is proportional and well harmonized. These control surfaces have little effect on yaw initially, and the result is a large dead band in the rudder authority. The rudders on the tipsails of the single-engine airplanes deflect outward only, and only on one tip at a time.
What was noticeably different from the XLT-5 handling was the rudder.
#ESA V TWIN ENGINE FULL#
The little bit of noise the full feathering MT composite propellers create converting horsepower into thrust is left in the wind behind the airplane. With mags and the prop feathering checked, all that remained to do was fly.
#ESA V TWIN ENGINE INSTALL#
On the prototype, a single boost pump fed both engines, but most likely builders will install a boost pump for each engine on subsequent aircraft. Both engines are fed from a single fuel system made up of two 48-gallon tanks in the wingroots and a 5-gallon header tank. Just like the singles, set the elevator one finger width below trail for two in the cabin and two fingers below trail for four.
The pitch trim is a spring system, and the elevator on the canard is in plain sight. Soon we were at the end of the runway and it was time to close the big gull-wing doors, runup and go fly. The second engine makes taxiing much more pleasant and precludes the need to drag a brake in all but the strongest crosswinds. Taxiing is accomplished with differential power, and brakes when needed. So single engine architectuur, but that doesn't work well with reusable.The two IO-320 Lycomings light up easily, and the composite MT propellers make little noise at idle power. (F9)Ģ400 or 3000kN multi engine is total overkill. Reusable, C (LOx-HyroCarbon) and 1000kN is a good match, aka multi engine architecture. (BE-4 = single shaft Raptor = dual shaft). A FFSC Methalox engine could be a next demonstrator, switching back to dual shaft. Don't forget, the budget for prometheus development was estimated at €100mln, and it isn't completely funded. If I'm not mistaken, the SC engine development (HTE) was droped because of lack of funding. Launch frequently is to low for volume production and reusable. I think C will be introduced and expendable will remain.
Within the 10-20 annual launches range, PHH expendable is for now the best solution in Europe. All combinations are used, so there isn't a clear best solution.' 'For bottles you have lots of different options.
So I expect the cost of Vulcan and Vinci can also go down a lot in the future.įor the Expendable / Reusable discussion lets write down the Jan Werner analoge: It's a total switch in technology, lots of these technologies can also be implemented into the Vinci, Vulcan and Myra engine production. Instead of maturing technologies using TRL, they switched to demonstrator programs to speed up the R&D & Introduction proces. I think Prometheus and Callisto are demonstrator programs, like Airbus Vahana the X3 helicopter, enz. By combining Prometheus and Callisto, a first stage reusable CC or CH Ariane Next could be developed. This CC could be part of the Ariane Next family. The first laucher that will use C is Vega-E (PPC), the second one is Vega-L (PC).Īs I've written before, the next launcher I expect is another PC, and a Vega replacement (PPC or CC). Prometheus will introduce C into the option equation besides H and P (Myra also does this).