VSKYLABS 'Test-Pilot': SR-71-TB - Air Refueling process explained:
Default air refueling process is not functional in X-Plane 12 (at the present...).
The VSKYLABS SR-71-TB refueling process is a temporary solution, which was selected after a long evaluation of various options. This was chosen since it is the least hassle-free procedure which allows straightforward refueling, as part of any mission planning, and it is also unlimited, as you can refuel multiple times like in the real-world SR-71 operations, where it flew really *long distance*.
It goes as follows:
Once the aircraft is set in the air-refueling pattern and envelope, and the air-refueling system is set to receive fuel, the KC-135 tanker will turn visible, while fuel is being received-in.
During the air-refueling process, fuel-level monitoring will show gradual increase, as well as other aspects (like CG indicator shows gradual movement backwards etc..).
Requirements for air-refueling:
Air refueling is not mandatory, and you can fly whenever you like, depending on your fuel levels and flight plan.
However, like it's real-world brother, the VSKYLABS SR-71-TB must fill its tanks *completely* while venting all existing air in the tanks. The reason is that if there is air in the tanks (tanks are normally pressurized with air), at high supersonic speed...that is above ~Mach 2.6, due to the high surface temperature of the aircraft, the air-fuel fumes will be ignited. Not a pleasant experience.
Completing the air-refueling process will assure that once the tanks are "air free" and fully loaded, Nitrogen gas (inert gas) comes in play for fuel tanks pressurization.
This is a *must have* condition that allows to proceed beyond Mach 2.6 towards the 80,000 feet / Mach 3.2 (and beyond) safely.
All of the above (and much...much more) is simulated in the VSKYLABS 'Test-Pilot': SR-71-TB Project.
Exciting development note:
During the air-refueling sequence, an authentic communication recording will be heard through the aircraft inter-phone/radio system.
The recording was sampled from a video, documenting BC Thomas in one of the air-refueling training sessions of the SR-71. It was edited and implemented into the VSKYLABS 'Test-Pilot': SR-71 project following Mr. BC Thomas direct approval.
Mr. BC Thomas - The famous SR-71 pilot with the most flying time in the SR-71 (1,217.3 hours), and is the only pilot to have flown all three of the Air Force's high-altitude reconnaissance aircraft (the U-2, RB-57F, and the SR-71).
In his explanation regarding the audio recording, Mr. Thomas told me that on operational reconnaissance missions, they conducted aerial-refueling operations in complete radio silence, talking to the tanker crew only on "boom inter-phone" after the rendezvous, and after establishing boom contact. In the case of the VSKYLABS 'Test-Pilot': SR-71-TB, all flights are considered 'training', so...the radio-communication is not an operational issue... 🙃
SR-71 Air Refueling video (training) - from BC Thomas YouTube channel:
