Standby Generator bug?
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Hi all,
I think I may have found a bug in the standby generator logic, and wanted to confirm it before raising a ticket.
The issue seems to be that the standby generator can power itself, by running the yellow AC pump and PTU, which then provides green system pressure to keep it running.
In theory, it shouldn't be possible to power the standby generator through the PTU, AFAIK
To replicate:
- Take a cold and dark aircraft
- Power via APU, external power
- Set AC yellow pump to On or AUTO and PTU to on
- Set Standby generator to override
- Remove APU/external power
Note: you can even disable battery power at this stage, the standby gen will continue to provide power.
Toggling the PTU or AC pump will kick the standby generator off again, but, if you're quick, it'll come back again too.
I also appreciate that its a bug that can only be really found by flipping switches willy nilly
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This is the correct logic for the 146. The standby generator is driven by the green hydraulic system and along with the standby inverter, will power the essential and emergency AC/DC busbars.
This means that if the AC busbars were to fail, electrical power would still be generated by the green hydraulic system via the standby generator and standby inverter. In this state, the aircraft would be in what is called the "essential power level" with the standby generator/standby inverter powering the ESS AC BUS, EMERG AC BUS, ESS DC BUS and EMERG DC BUS. As the power comes from the green hydraulic system, the batteries aren't being drained and therefore, there is no flight time limit in this state but there will be limited system functionality.
If there was some catastrophic failure that took out the electrical and hydraulic systems, the batteries could then be used as a final redundancy until they were completely drained.
A description of the standby generator and standby inverter is included on pages 46 and 47 of the 146s Operations Manual: https://downloads.justflight.com/products/JFF003642/146_Professional_MSFS_manual.pdf
Mark - Just Flight
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So I followed the OP's steps and end up with the overhead like this:
Note that engines, APU, batteries, and external power are all off. The only thing that's running are the standby generator and inverter, effectively powering themselves through the hydraulic system. If that was correct, BAe would have solved the world's energy supply decades ago 😂
The only way I could see this work was if the standby inverter was powered off a battery hot bus? That system needs to get energy from somewhere.
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Apologies I misread the original post (I'll blame Monday mornings for that)!
Thanks for reporting this. We have been able to replicate this and we've logged this on our internal bug tracker and we'll investigate ahead of the next update.
Mark - Just Flight
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Thanks @Laurreth for the screenshot, in hindsight, that would've been helpful!
I found the bug when I'd just bought the 146 and wondered what would happen if all the engines stopped, and how well it'd fly.
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@BAEflyer The electrical system is fully custom-coded in the 146 Professional. It has been coded based on the extensive research material we have access to, including FCOMs from the real aircraft.
The bug reported in this thread is with a non-normal procedure and it hasn't previously been reported by anyone in our beta team, or with the thousands of customers that own the aircraft in the 2+ years that the product has been available. We have acknowledged the bug, we have replicated it and the fix will be included in the next update to the 146 Professional.
If you find that some of "the most basic dependencies" in the aircraft don't work please contact our support team via the following link and they will be able to assist with troubleshooting that with you: https://www.justflight.com/support
Mark - Just Flight
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@Mark I fully aware of the fact that it is a high fidelity product at an amazing level of detail. I enjoy using it on an regular basis. And I am aware of the fact that it tries to simulate an entire airplane.
However, the problem discussed here is as much a bug as running the engines with the cutoff switches "off" would be considered a bug, given the "custom coded environment."
I'm also aware that literally thousands of users won't even bother. You just have to look at the number of voters for any given topic in the msfs forum. Those with the most votes are in the hundreds, at most. Which is incredibly tiny compared to the millions of users. Based upon these figures it doesn't even make sense to maintain a forum in the first place. If you choose to do so, well ...
I'm holding back on things I encountered because I'm also aware of how irrelevant they probably are in the grand scheme of things.
But if you insist: the random failure system (still) doesn't work. I haven't had a single failure on "high". Not even in a given amount of time, but ever. There's other threads/responses about that. I chose to not open a ticket about it because it by now you must be aware of that, i'd guess and have probably other, admittedly, more important things to do (developing three planes at once). But on the other hand: I as a customer can't really be blamed for trying it out and finding it in a state in which it simply doesn't work. You guys chose to implement failures. Okay, didn't ask for it, obviously others did. Also, others mentioned that most failures don't do anything besides illuminating the respective warning light. I was one of them, btw! (TMS working flawlessly after being failed manually!) This was not a bug. Just like a car not starting upon turning the key is a bug (for lack of a far better comparison) How am I expected to react to this? How does this pass QC? Does it get a "nobody will notice it anyway-stamp"?
I'm a loyal customer, and will be in the future, because your products are good, even amazing products. But ye who says "a" must also say "b"
Literally translated from German. Sorry if it doesn't make sense.
And yes: I DO have a job and a life. No kids though ...
Kind regards
Manuel -
Loss of both main generators will (providing the green hydraulic is operating) trigger the STBY GEN to operate. The normal GREEN HYD systems are ‘lost’ in favour of running the STBY GEN. One of the first check list items will be to select the PTU ON in order to support the STBY GEN.
With the a/c now at the ESSENTIAL POWER level, the fun start! Amongst the joys to come are EMGY GEAR lowering, use of the STBY GEAR indicator lights, no airbrake, yellow spoilers only, loss of nose-wheel steering, half speed flaps, and calculating landing distance required.
