I don't know if this is the right place to post this or not - but here goes.

Monday I had the privilege of sitting in the "bosses'" seat (right rear), While my two adult sons (recently minted Commander Pilots), sat in the front!!!! They did a great job! I am a very proud Dad.

But I am also writing about some figures that we collected on this trip, and I wanted to see if they could be correct and if you all agree with them. We flew from Deland, FL to St. Cloud MN on Monday. It was a particularly brutal flight since we had 80 to 90 knot head winds almost all the way, aaaaaand we chose to deviate for some significant turbulence.

The flight lasted 5 hours and 47 minutes. When we topped off with fuel for the trip home we put 374 gallons in our 81' 840 with dash 10 engines and optional extra tankage 475 gallons total. This means we had 101 gallons remaining when we landed. We flew the first half of the trip at about 286 knots true, burning 440 lbs per hour. We contemplated stopping for fuel and decided that if we could land with 1 hour of fuel - we would continue to the destination. If we calculated less than an hour reserve we stop for fuel.

We came up with the idea of pulling the power back a little bit, and see how that looked. We pulled the power back to 275 knots and the fuel burn was 400 lbs / hr. Sooooo, on this flight we had an ultimate of 7 hours and 28 minutes of fuel!!!! This is absolutely unbelievable to me.

I know this is rough math but - 3,100 lbs of fuel (75 for taxi etc.) burning 400 lbs per hour @ 275 kts works out to 1,856 NM - leaving 1 hour of reserve fuel at the destination. I know there is some climb fuel in there, but there is also some descent fuel savings. But either way - that is just unbelievable!!!!

Now one more thing occurred to me on our return flight home. We talked a lot about taking off over gross. (The unspoken thoughts of the Commander community). I was thinking that if we left 70 gallons out (35 gallons from each wing) we would save 469 lbs. Add to that the 75 lbs for taxi - plus my airplane has about 36 lbs of payload left with full fuel - That leaves 505 lbs for people and bags. (Not too unacceptable in the general aviation world.)

So the moral of this long story is, by throttling back just 11 to 25 knots (depending on temperatures and day, I can be "legal" / safe (er) and still have 6 hours and 30 minutes endurance with 1 hour of reserve and still have 1,552 miles range (no winds of course).

I know in one sense this is obvious leave off fuel - if you have a big load, but it never occurred to me to pull the power back slightly to pick back up some range. Another point is - not that many people want to sit still for that many hours. But once in a while the situation might arise.

Or the counter point. The airplane is so overbuilt just fill it up and go. The over weight issue is fixed in the first hour - right?

Thoughts?