$1 billion BMS Ooops...

One thing a motorglider allows you to do is to select safer landout sites - not because you can motor away from a bad one, but because retreating towards a safer area, while still high, has less risk of inconvenience. A fair number of landouts in bad places can be attributed to wanting to get closer to home to have the retrieve be shorter, passing up better - but further away - choices. We had two landouts in a lake last year which probably had this as a component in the decision making. With the possibility of a motor start, retreating towards a nice safe paved runway does not have the same consequences for the rest of the evening.

When you are thinking about that final glide in sink, remember that pulling the motor out to start it will cost you a few hundred feet in altitude, even if it fails and you are able to put it away again. If it fails and you are unable to put it away, you've just given up about 1/2 your glider performance. On my glider the difference is 50:1 going to 20:1. The jets are a bit better and an FES better still, but there is still consequence, even if it is just a distraction from efficient flying. This is a real dilemma on a marginal final glide in a motorglider. I don't have a comfortable glide. Should I pull the motor out now while I still have enough altitude to try to deal with the consequences? If it doesn't start I will for sure not make it.. Should I have pulled it out 5 minutes ago? Too late now - will I regret, 5 minutes from now, not having pulled it out now? All these things run through your head.

On Tuesday, March 9, 2021 at 3:53:52 PM UTC-8, John Johnson wrote:
On Tuesday, March 9, 2021 at 1:55:27 PM UTC-7, jfitch wrote:
If you are thinking of a motorglider as saving you from an unsafe landout, you are a Statistic - In -Waiting. What a motorglider does is save you the inconvenience of a safe landout and retrieve. If anything, it makes landouts more dangerous, as the pilot workload at a critical point increases (and this is an argument for electric, which typically takes less attention).. A motorglider does not increase your range over unlandable terrain, or improve your chances for a safe landout (not reliably, anyway). Your example of continuous 7 - 9 knot sink for example, would be turned into continuous 5 - 7 knot sink with a typical sustainer, and it would take the most powerful of self launch power plants to turn that into a climb (even if you are lucky enough to have the motor start). A motor is no substitute for intelligent decisions, and it is not a substitute for having an easy glide angle to a safe landing site at all times. I have two friends with motorgliders left in trees that can bear witness.

Agree with all your points and I don't think I've ever seen a motor related thread that doesn't preach the obvious: don't rely on your motor to keep you safe.
I'd also mention out there's a large difference between 'safe' LO sites. Some offer convenient accommodation (wide-open approach, smooth surface, room for a long roll-out, aerotow retrievable, drive the trailer onto the field, beer nearby, etc). Others are more challenging but ultimately safe for the pilot. Challenging LO's include short fields, glider scuffing through low vegetation, bouncing across uneven surfaces, losing a gear door in a freshly plowed field, unexpected livestock, locked gates, no trailer access, needing you and your crew to attend a mine safety class before being allowed to retrieve your glider, etc.
I don't think these types of LO variations are particularly unique to AZ. It's part of our XC decision making process and risk assessment. It's important to always have a safe-for-the-pilot LO option. I make sure I do. Just like I did in the example I provided. But there are many defined safe LZ's in our area that you would definitely prefer not to land in. I'm very well acquainted with the distinctions and tomorrow, I'll be out on my 4th all-day land out survey expedition to document this season's current LZ conditions for a segment of our club's usual XC operating area. Having 100's of hang gliding XC 'land outs' with no prior LZ familiarization just doesn't cut it now that I'm flying gliders XC.
I did a bit of math using my recent example's igc log. I assumed that I turned a motor on at 5mi out (10mi into that final glide - the point which I clearly knew the highly undesirable mine tailing land out was a distinct possibility). With average sink rate changing from 8kts to 6kts - I make the field just below pattern altitude. While that's nice to see, it's a whole lot closer that I would have assumed and your point regarding limited glide improvement is a good one - thanks.

JJ