Steve Brown
Well Known Member
This is probably not as thrilling to others as it is to me, but I was completely surprised. I learned some things about my airplane and it forced me to expand my fuel management skills.
825.8nm
5.4 hours
32.48 gallons
ind alt 15,500'
DA ~17,400'
TAS ~ 147
I had planned a fuel stop at KDTA, but before I got there I noticed my fuel burn was well below plan. After crunching the numbers I realized I could make it all the way to KAPA with acceptable reserves. My estimate was that we would make it with about 45 minutes reserve, maybe up to an hour.
I had ran the left tank dry near KEGE. On landing we were showing about 4 gallons remaining in the right tank. The fuel fill implied we had only 3.5, but I think the tank holds a bit more than 18.
Our average fuel burn was 6 GPH, including climb, so even 3.5g was greater than 1/2 hour reserve. We lost some of our tail wind on the second half of the trip that ate into our margins.
Some notes:
I've been experimenting with running LOP for the past few months. When the MP is pulled back to an inch or two below max it works great. For this trip I only pulled back a bit more than 1/2 inch. My leaning procedure was not very scientific. I leaned until roughness, then enriched it just a bit. I noticed this was just LOP on #3, which I think was my leanest cylinder.
**
Running a tank dry was a first for me. I was a bit apprehensive, but being within glide of an airport made it emotionally easier. When I was showing about 1 Gal remaining, I switched on the fuel pump. When fuel pressure started to drop I switched tanks. To my delight the engine never missed a beat.
My wife was not happy with this procedure at all. Adding to the apprehension is that it ran a long time, maybe 10 min while pegged at zero. Anyway, it had to be done. Using all the fuel in that tank is what allowed having acceptable reserves on arrival. Now that I've done it, I wouldn't hesitate to do it again.
Another note on this procedure: pay attention to the fuel pressure gauge! I was watching it close and got distracted by ATC. I heard the pump struggling and by the time I looked at the pressure it was falling fast. Not a catastrophe if the motor quit momentarily, but its drama I don't need.
**
I've been checking the fuel gauges on this airplane since I bought it. They are very accurate. That gave me the confidence to use them for in flight fuel planning
**
The GPS496 is what tipped the balance on making this trip non-stop. Otherwise, I wouldn't have had the nerve. Continuously updated ETE + weather. Weather means wind, so I new what to expect. We also had to skirt several small thunderstorms. The XM weather allowed doing that, and in an economical way.
825.8nm
5.4 hours
32.48 gallons
ind alt 15,500'
DA ~17,400'
TAS ~ 147
I had planned a fuel stop at KDTA, but before I got there I noticed my fuel burn was well below plan. After crunching the numbers I realized I could make it all the way to KAPA with acceptable reserves. My estimate was that we would make it with about 45 minutes reserve, maybe up to an hour.
I had ran the left tank dry near KEGE. On landing we were showing about 4 gallons remaining in the right tank. The fuel fill implied we had only 3.5, but I think the tank holds a bit more than 18.
Our average fuel burn was 6 GPH, including climb, so even 3.5g was greater than 1/2 hour reserve. We lost some of our tail wind on the second half of the trip that ate into our margins.
Some notes:
I've been experimenting with running LOP for the past few months. When the MP is pulled back to an inch or two below max it works great. For this trip I only pulled back a bit more than 1/2 inch. My leaning procedure was not very scientific. I leaned until roughness, then enriched it just a bit. I noticed this was just LOP on #3, which I think was my leanest cylinder.
**
Running a tank dry was a first for me. I was a bit apprehensive, but being within glide of an airport made it emotionally easier. When I was showing about 1 Gal remaining, I switched on the fuel pump. When fuel pressure started to drop I switched tanks. To my delight the engine never missed a beat.
My wife was not happy with this procedure at all. Adding to the apprehension is that it ran a long time, maybe 10 min while pegged at zero. Anyway, it had to be done. Using all the fuel in that tank is what allowed having acceptable reserves on arrival. Now that I've done it, I wouldn't hesitate to do it again.
Another note on this procedure: pay attention to the fuel pressure gauge! I was watching it close and got distracted by ATC. I heard the pump struggling and by the time I looked at the pressure it was falling fast. Not a catastrophe if the motor quit momentarily, but its drama I don't need.
**
I've been checking the fuel gauges on this airplane since I bought it. They are very accurate. That gave me the confidence to use them for in flight fuel planning
**
The GPS496 is what tipped the balance on making this trip non-stop. Otherwise, I wouldn't have had the nerve. Continuously updated ETE + weather. Weather means wind, so I new what to expect. We also had to skirt several small thunderstorms. The XM weather allowed doing that, and in an economical way.
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