The Commander has two 24v batteries. By doing a parallel start, which is the normal start, you send 24v to the starter generator to spin engine up. Normally this is enough. But if for some reason engine doesn’t spin up fast enough to be able to self sustain and start, you can put the batteries in series and send 48v to the S/G. This spins it up faster, but also depletes battery more. Normally reserved for cold days when oil is syrupy, or when starter/generator is old or on really hot days when you’ve flown her before and want a really fast start that puts a lot of calling air through the engine. It’s normally a tell tale sign the S/G is getting weak when you have to resort to that at normal temperatures.
Sebastian,
Thanks, glad you enjoyed it.
>>>Why did you fly the southern route CYYR – BGBW – BIRK while you cam from the weat coast? I think a routing further north would be quite a bit shorter.
I’m not anything approaching expert in these things, having only done it once, and that time was in the company of a pilot to does ferry flights for a living… but will take a stab at this based on my recollection. We played around with alternate routings, which would have meant less flying time due to shorter distance and less time in the air, but the alternatives didn’t change our expected day of arriving at our destination and had other hassles, given the set of variables we were working with. CYYR (Goose Bay) – BGBW (Narsarsuaq)– BIRK (Reykjavik) is pretty bog standard and is generally referred to as the Northern route. We wanted to do this portion of the Atlantic crossing, setting off in the morning and within a single day, possibly as a single flight, depending on winds and weather. We were non-HF and that restricted us to specific routes and altitudes (I seem to recall that in our case it was 25,000 feet minimum for CYYR-BGBW). We did plan the trip to have minimal unnecessary time over areas with no safe landing options and we didn’t want to combine no landing options with night flight. We also needed to choose ports of entry and exit for the U.S. and Canada, and there were issues with hotel availability at some of the Canadian towns.
Based on our original plan, incorporating the variables of aircraft range, hotel availability, hours of daylight… our chosen route made the most sense. Between California and Greenland a more direct routing would have saved some time in the air but as I seem to recall it wasn’t going to get us to Cannes any earlier. I’ve just spent some time playing with ForeFlight, trying to recall exactly why we didn’t go more direct across North America… a direct across Northern Canada and then launching across the Atlantic from Iqaluit (CYFB) would have been shorter. It would have meant more time off the beaten path and over inhospitable terrain, though.
>>>I clearly have a commercial interest in this but did you really land at BGBW just to get a weather update? With data link weather you could probably have avoided this stop and saved a lot of money and time.
In a good scenario, with better weather forecast on route, we probably would have filed for BGBW as our destination with BIRK as our alternate. Then, we would have made a decision approaching Greenland whether to continue to BIRK based on actual winds aloft and actual fuel consumption. Doing CYYR – BIRK safely was going to require a good tailwind, it is beyond the aircraft range, even before factoring in IFR or VFR reserves, in a wind calm scenario. We did the safe thing from a fuel planning perspective by stopping at BGBW, as well as from a weather planning perspective. We did want to check the progress of a storm front which was towards the path of BGBW – BIRK, which had some vertical development through our cruising altitude with probable icing. Long way of saying that I think we probably would have stopped at BGBW, even with onboard weather. I would have liked to have onboard weather data and am looking at your product or just getting an iridium data/phone link thingy (I’m not very far along in the shopping and am not up on the exact technical lingo…)
>>>Finally how did you make sure the engine problem was really the starter-generator? It would have been a pitty to wait days for a new one and then to find out it is some other part. Did you swap the generators left to right to check?
I’m pretty sure we did try swapping them, although, I can’t remember as it has been a while. We trouble shot the problem, to eliminate the possible alternatives. But once we removed the right starter generator it very was obviously toasted… I will post a picture, there were droplets of melted metal falling out of it, it was done…
Sadly I’m grounded at the moment, after some very clumsy thieves got into my plane while it was parked at Fairoaks, and unsuccessfully attempted to forcibly remove my entire panel, destroying lots and lots of things in the process.
That is terrible, sorry to hear that. Do you have insurance …?
Alexis, yes I do, thankfully and this is covered.
At least every now and then it pays off to be covered well … Good luck!
How’s the panel repair and avionics replacement coming, Patrick?
What the heck is it with these kind of stories in the UK? Makes me glad to be at a secure airport with my parking. If you cannot trust an aircraft to be safe then an airport like that is pretty much useles.
Yes, I’m thinking similarly at the moment…
