Confusion over tutorial video alternator isolation
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Hi, In the tutorial video 2 Starting the engines after starting the engines all the alternators are turned on but then 1,3 and 4 are isolated leaving 2 connected but then after taxiing to the runway at the hold point where you do a final check of the AEO station, all alternators, including 2 are isolated so could you please clarify if this is correct because there is no mention of having to isolate the number 2 alternator after initially saying it should be isolated.
Thanks -
@Jayviator Good spot, it looks like I may have missed a step in the video there (that's me told for using two separate recording sessions to create the video! 😅 ). I'll attempt to clarify the process of connecting and isolating the Alternators below:
For takeoff and landing in the Vulcan, only the AAPP Alternator should be connected to the synchronising busbar. All engine alternators should remain disconnected.
During the After Start Checks, you need to disconnect the external equipment (Houchin Ground Power Unit and Palouste Air Compressor) and to safely do this you need to press the EXTRA SUPPLIES TRIP button to disconnect all the external supplies from the Synchronising Busbar (which includes the AAPP) before then deselecting them on the EFB. As a fail-safe to ensure the aircraft has a continuous supply of electrical power, this process will automatically connect the No.2 Alternator to the Synchirnising busbar which we see in the video. What isn't shown in this video, is that you should then press the AAPP ON button again to reconnect the AAPP Alternator to the Synchronising Busbar, and then isolate the No.2 Alternator (which takes us to the point of the final check of the AEO position prior to takeoff).
Hopefully, that helps clarify the process. If you get stuck when in the sim, I'd recommend having a look at the MSFS checklist menu which is supported by the Vulcan, and that should walk you through this process step by step and highlight all the buttons/switches that need pressed/moved.
Mark - Just Flight
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Hello, thank you for your reply. I think I have it figured now thanks to your help, but would like to confirm that up to the point where you disconnect the external supplies by pressing the extra supplies trip button, the procedure of isolating all alternators but connecting the No.2 Alternator is still correct?
Cheers
Jay -
When the EXTRA SUPPLIES TRIP is pressed, that would automatically isolate all external supplies and would automatically connect the No.2 Alternator to the synchronising busbar to ensure electrical power isn't interrupted.
With no external supplies connected, the real aircraft checklist then calls for you to synchronise all alternators, check load sharing, and then isolate No.1, 3, and 4. You then need to reconnect the AAPP by pressing the AAPP ON button (which is the step skipped in the tutorial video) and that will automatically connect the AAPP Alternator and isolate No.2.
From the 'After start checks' section of the real aircraft checklist:
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AAPP . . . . On synch bar
a. Within limits
b. ON button pressed (1 second max)
c. Check indications -
Extra supplies trip . . . . Press, No 2 alternator on synch bar
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External supplies . . . . Removed
a. Palouate
b. External 200V
c. External 28V -
Alternators . . . . Load sharing checked. No 2 on synch bar
a. Synchronise all alternators
b. Check load sharing, kW /kVAR
c. Isolate No 1, 3 and 4 -
AAPP . . . . On synch bar
a. Within limits
b. ON button pressed (1 second max)
c. Check indications
Mark - Just Flight
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