BAC-111 Pneumatic System

[investdude]

Thanks for the information David. I'm sorry that you're not going to be doing any more updates to the BAC-111 panel. I've played around with the systems for a while now and actually most are working pretty much as they should except for the pneumatic system. For instance, I tried failing the No. 1 engine with the no. 1 AC hydraulic pump off and, sure enough, the gear does not come up when selected but does come up with the pump on, exactly as it should. So the pneumatic system seems to be the only one that needs a little work to bring it up to scratch. Perhaps there's somebody out there with the requisite skills who could take this on, with David's permission of course?

[Independance]

I start out cold, start APU, open the air delivery valve and get a pressure indication on the pneumatic system left side which is correct because the APU air comes into the left side. But when I open the crossfeed valve the right side does not show a pressure rise. Now it's 28 years since I flew the airplane and I could be forgetting something but that doesn't seem right to me.

When APU running and crossfeed open throw that other switch on APU panel. I have never flown the real thing and don't know if it is correct but in FS2004 it definitely works. You will get pressure on both sides.

Tomasz

[investdude]

When APU running and crossfeed open throw that other switch on APU panel. I have never flown the real thing and don't know if it is correct but in FS2004 it definitely works. You will get pressure on both sides.

Yes, you do get a pressure indication on the right side at other times but not when you start out cold, start the APU, open the air delivery valve, then open the crossfeed valve. Some of the relevant switches are probably not programmed in such a way that the indications are correct. The other switches relevant to the pneumatic system are the isolation valve switches and the MAC valve switches. The way the system was operated is as follows:

After the APU is started and used to power the system via the air delivery valve and the crossfeed valve, the MAC valves are both placed on APU. No other actions are required for the system until just after take-off when the system is switched over from the APU to the engines as follows: no. 2 isolation valve open, no. 2 MAC valve open, crossfeed valve close, no. 1 isolation valve open, no. 1 MAC valve open, air delivery valve closed. After at least a minute's delay to allow the system to adjust, the APU is shut down for the rest of the flight until just before landing when the APU is restarted and the system reconfigured as above in reverse so that the APU is powering the system for the landing and the full power of the engines are available in case of an overshoot.

I think some of these switches are not programmed quite correctly so that some of the indications, eg. pneumatic pressure and MAC valve lights, don't indicate quite correctly for the configuration. It would sure be nice if somebody could undertake to fix this because this simulation is so good in every other way, the handling and feel of the aircraft is amazingly true to life.