Forced Landing/No fuel

[atsiii]

Thank you all. There are important dialogs and ponderings, so I will endeavor to answer as many of your questions as I can.

Bob Cook..

1) Yes, the FAA came and confirmed remaining fuel. There was essentially nothing usable in any tank (maybe an oz. or so in one of the mains.) The two aux tanks had about 2 gallons of un-usable each, and the mains had much less un-usable, perhaps 1/2 gallon or less, each.
2) Yes and no... the Cessna fuel quantity guage for the right main finally caught my attention about 50 miles out. It just seemed to be indicating lower than normal. So I switched the rear to the right aux to simply finish whatever was there. I estimated there would be about 5 minutes of fuel in the aux, but we only got about 2 minutes of operation. Then I switched the rear back to the right main. Strangly, about 20 miles out, the front engine then started failing (it's guage still looked normal!). I tried switching it from the left main to the right main and turned on the front engine boost pump. but I could not keep it running. I could have (probably should have) switched the front to the left aux, but after having just seen that there was only 2 minutes left in the right aux, I didn't. I feathered it. The rear started failing with 90 seconds of feathering the front. We had only about 1500 AGL, so it all happened pretty quickly.
3) I'm not familiar with a "minimum for takeoff" placard. No, I deal only with usable and figured I was missing +/- 12 gallons.
4) The mis-allocation was for start-up, warm-up, taxi and run-up. I had allocated 2 gallons (based on an average of 10 minutes). My Flitesoft Professional also used 2 gallons, and also said I should have plenty of fuel. When I finally figured out what had happened (with the four cold starts in four days), I found in Flitesoft Professional where to change this allocation. It is in Weight & Balance for the Aircraft settings. Along with the station and arm, you can enter startup gallons used. When I change this from 2 gallons to 5 gallons, sure enough, it confirms what I confimed with flight tests... there was not enough in the tanks to make it home!
5) In this case, A totalizer "would" have let me see the cumulative affect of the multiple cold start/warm up consumption. In seeing that, the accident would have been avoided. You can rest assured I will buy one!
6) Regardless of buying a totalizer, as Ernie says, henceforth I will also dip each tank before every flight. You have to know what you are starting with. Yes, people do siphon fuel... and FBO's do short you gas (charging you for 80 gallons and only pumping 70 gallons on board). My airplane allows for dipping tanks, so I will do so. I will spend however long it takes with a gas truck here to add known quantities and then mark the dip sticks, accordingly.
7) My fuel flow guages are actually amazingly accurate. I can set the fuel flow based on the JPI lean find, then write down the hobbs and indicated fuel flow. When I multiply it out at time of topping off, it's dead on. My quantity gauges are worthless, however!
8) I think Jim talked about adding more allowance when making numerous short flights. That was my failing!
9) Also, please remember... all this notwithstanding, I still departed with intentions of getting more fuel 50 miles away. Only because mother nature baited the trap by giving us 190 kts groundspeed and the promise of a 1 hour flight home (when I incorrectly thought I still had 1.5+ hours on board!), did I make the in-flight decision to simply head home direct.
10) Jim & Larry... Jim, you are correct. That's what I normally do. Larry, you are correct, these were not normal flight profiles. In fact, since we only had an hour home... this time my bladder was only 1/3 full when my tanks were empty!
11) Guy... agreed. Again, accurate cumulative fuel flow data would have shown me what was going on and avoided the accident. But I didn't (at the time) have a way to accurately dip the tanks, nor did I have a totalizer. My hobbs time & burn has also always been very accurate... and based on my hobbs, we should have made it home with 12 gallons or more to spare. But I was off on the startup, warmup, taxi and runup... by about 3 gallons per cycle. And that's where my 12 gallons went!
12) Paul... it's not a bad method at all, but I like to use my aux tanks on every flight so I know when I switch to them and hit the boost, they will deliver as promised. I always time my use of them, calculate how much should be needed to replinish them, then compare that to the fuel ticket. I just didn't know my airplane took closer to 5 gallons from a cold start to wheels up, and not 2 gallons. I'm simply suggesting that in addition to time & burn, everyone think about cold start consumption and number of operations between topping off. Because the hobbs is not moving then!
13) Dale, I suspect I will start watching now, too. I usually just compare the fuel ticket to my calculations to make sure they put on as much as I expected. But you can bet I will start watching now.

Thanks, all!

Allen

[hewilson]

Thanks for the lesson Allen. I'm a student pilot and wannabe Skymaster owner. I've read a lot about fuel exhaustion as an accident cause in GA and specifically in Skymasters. I've often wondered how it could be so difficult to manage fuel. Your post and the subsequent discussion have gone a long way toward furthering my understanding of the problem.

That having been said, I'm also very interested in the details of your forced landing from 1500 agl. Did your emergency procedures come back to you quickly? (Given your safe landing, it would appear so) Do you feel that you completed the entire check list? Were you able to maintain optimum glide speed? Was the landing rough? How was your pucker factor? I'd be very interested in the landing part of the story if you would feel comfortable posting it here. Thanks again.

Hugh