The SR-71 AG-330 Start Cart was fitted (initially) with two Buick Wildcat 401 cubic inch, 400 horsepower V-8 engines. These engines were positioned in tandem and were linked together, driving a vertical shaft inserted into the SR-71's engine starter mechanism.
During the SR-71 engine start process, a single AG-330 unit was used for starting each of the SR-71 engines.
When engine start process was initiated, the pilot communicated with the Crew Chief to engage the AG-330. The AG-330 operator activated the ground starter. The pilot monitored the given engine gauges, waiting for the RPM to rise. Once engine RPM came "alive", he set throttle to idle.
When shifting the throttle from cut-off to idle, a 30cc of Triethylborane (TEB) was injected into the burner cans, producing a characteristic green flame (which is being simulated and visualized in the VSKYLABS SR-71-TB). The J-58 engine ignited, accelerated, and brought to life. Once it was running, the AG-330 unit was shutdown. The process was identical for both engines.
Important:
The SR-71 is not equipped with on-board starter/APU or other means of mechanical engine-start. No switches for 'starter' exist. The VSKYLABS SR-71 is just the same. The starting process was customized in X-Plane 12, to allow similar engine-start experience: The pilot clears for the AG-330 starting sequence, the RPM rises, TEB is injected when the throttles goes from cut-off to idle, and that's about it!
The VSKYLABS SR-71-TB can be started in cold-and-dark in the following methods:
Using X-Plane auto-start (ctrl+shift+e):
- Set both throttles in the cutoff position.
- Initiate auto-start.
- AG-330 will be triggered, LH engine first.
- Monitor RPM. At about 10-20%, set the LH throttle to idle (slowly but firmly). The TEB counter will show a single TEB injection, and the engine should come-alive.
- Once the LH engine is alive, initiation of the RH AG-330 is AUTOMATICALLY. Monitor RPM and manage the throttle the same as with the LH engine.
- Once the RH engine is alive, up and running, the AG-330 will shutdown automatically.
Interacting with the RPM gauges (clicking, working only in cold-and dark): Process then will be the same as described above.
Interacting with the AG-330 in external view mode: Process then will be the same as described above. Make sure to advance the throttles in sufficient RPM).
*The start-up process is detailed in the SR-71 checklist along with other related actions, and can be practiced in the VSKYLABS SR-71-TB.
