Why do pilots push fuel endurance....

mscard88

mscard88

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This guy ( a CFI!) flew for 3 1/2 hours in a C152 and ran out of fuel. He's fortunate he landed and is alive. A 152 burns around 5-6 GPH and has 24.5 gallons usable. Like VFR into IMC, this one happens way too frequently and is preventable. Article says he used 5500' as a cruise altitude, hmm, from St Augustine to Lawerenceville is NW, so as a CFI he flew at the wrong altitude for direction of flight also.

https://www.ntsb.gov/_layouts/ntsb....ev_id=20160118X02647&ntsbno=ERA16LA091&akey=1
 
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Agree it happens way too often. All I can think of why is denial or ignorance - they either refuse to accept that they're not going to make it or they don't know that it's a problem.

I don't know what the CFI started with - under full tanks, at 6 gph, a 152 should be able to go 3.5 hours and have a 30 minute reserve. Obviously he didn't have that much, which puts this under the ignorance category. He didn't have the fuel and didn't know it. Or he had a stronger headwind than expected and didn't accept that a fuel stop would be necessary.

Same way my solo airplane, 81917, died.
 
I'm not sure it's so much "pushing" as it is poor math skills or simple complacency.

I'm sure someone said to himself, "Self, if I really hope hard enough then I can make it to that next airport."

More likely it's not even a consideration until that first engine stumble.

About 10-15 yrs ago someone landed on a road around here in the middle of the night. The NTSB report was interesting. Aircraft had xx gallons, fuel burn at full rich was yy gallons per hour. Airplane ran out of gas in xx/yy hours...exactly. Probable cause: improper leaning.

Another time a plane I used to rent landed in a field. NTSB added up the fuel receipts for the weekend, added up the Hobbs time, and did the math. The answer they came up with was that the airplane would run out of gas right where it did.

There was a fatal near here a couple years ago. Night flight, and I haven't seen the final NTSB report yet. Speculation is: The pilot had made this trip many times before, and always had plenty of fuel. That particular night winds aloft were giving a very strong headwind. Pilot might not have been paying close attention to the timer since there had always been plenty of fuel for a non-stop in the past.
 
bflynn said:
Agree it happens way too often. All I can think of why is denial or ignorance - they either refuse to accept that they're not going to make it or they don't know that it's a problem.

I don't know what the CFI started with - under full tanks, at 6 gph, a 152 should be able to go 3.5 hours and have a 30 minute reserve. Obviously he didn't have that much, which puts this under the ignorance category. He didn't have the fuel and didn't know it. Or he had a stronger headwind than expected and didn't accept that a fuel stop would be necessary.

Same way my solo airplane, 81917, died.
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This guy must have been a little too sure of himself. He's a Comm/Instrument, MEL, CFI, and even has a type rating.

I've always told students/pilots to be on the ground somewhere getting fuel at the 3 hour mark in a C152. Use time, not what's indicated on the crap fuel gauges in the cockpit.
 
Cuz just like "E" in my car doesn't REALLY mean totally empty...I still got a few gallons
 
An unflogged 150 won't burn much more than 5 gallons an hour. Should have been able to do that flight with reserves. Should have been able to fly more than 3.5 hours. Even burning 6 an hour you've still got your reserve after that. Either he was flogging the poor thing, didn't start with full tanks, or there was something amiss with the aircraft to start with.
 
My personal limit is 1 hour's fuel after landing. It's been maybe 15 years ago or so but I remember really sweating it out when I discovered toward the end of my flight that I wasn't going to land with enough (personal) reserves. I realized I was a little behind schedule when I passed my last opportunity to refuel. I landed with slightly more than 30 min's reserve. An action I haven't repeated since. So yeah, I can see how it would happen if you're using the regs as your min.
 
My personal rules are to take the most pessimistic of the fuel gauge, my fuel flow meter, and my pre-flight calculations.

My favorite was a guy who was flying in someplace and had filed that he had 7.5 hours of fuel on board. At 7.6 hours he ran the tanks dry. I gave him some points for getting the fuel burn right. The problem wasn't within gliding distance of the runway when he ran it dry.
 
I have an answer but you won't like it: people are dumb. Get used to it. It ain't gunna change. The government is making sure that the average IQ is dropping steadily and dumb people are allowed to reproduce as much as they please.
(just think of the opening scene of Idiocracy, one of the greatest documentaries out there)
 
I've seen people "top off" the tanks and leave 1/2 inch of air space at the top. Pilot might not have leaned adequately or at all. Even these things considered, a 275nm flight is a stretch for a 150/152, even without a headwind. I have flights of that length but I have extended range tanks and fill them all the way up (35 gallons).
 
steingar said:
An unflogged 150 won't burn much more than 5 gallons an hour. Should have been able to do that flight with reserves. Should have been able to fly more than 3.5 hours. Even burning 6 an hour you've still got your reserve after that. Either he was flogging the poor thing, didn't start with full tanks, or there was something amiss with the aircraft to start with.
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What are you basing that on? Have you ever done a long XC in one? It might be 5 on an hour-long training flight where you spend 15 minutes on the ground, but it's much closer to 6 or even a bit over 6. Without leaning it could be well over 7.
 
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I was surprised once upon a time by the actual fuel burn in an O-235 powered Tomahawk. Same engine as in the C-152. I burned right at 7 GPH on a lengthy X/C.

The amount I fuel they added at my destination was sobering.
 
I seldom use the fuel gauges at all, due to their high inaccuracy. Grab a ladder, stick a fuel rod into the tank and visually verify the fuel level before each flight. A conservative fuel burn in the 152 is 7 GPH and 8 on an O-320 Cessna 172. Log the fuel added before the flight and monitor the time elapsed since.
 
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It's really simple. I've got 4.5 hours endurance on full tanks at performance cruise, and I never fly a leg over 3.5.

An hour's reserve is a great comfort zone. :)
 
Complacency the more ratings some pilots get,the more complacent they get. It can also be about the money ,trying to stretch to an airport with cheaper fuel.
 
I have never been able to understand this myself. I often find I'm tankering fuel around, but I would rather do that than the alternative...
 
Too many pilots figure miles rather than hours when it comes to how long the go-go juice will hold out. Throw in a little “adverse winds aloft” into the mix and Capt Dumdum just went bingo fuel over inhospitable terrain. There’s shame in turning back. Dead bodies feel no shame, nor do they learn any lessons. They can teach a few to those willing to listen, though.
 
I have 64 gal, the minimum I’ve gotten down to is 20 on a 5.5 hour flight... I don’t know, how wonder how many have run out of gas in their cars?
 
dmspilot said:
What are you basing that on? Have you ever done a long XC in one? It might be 5 on an hour-long training flight where you spend 15 minutes on the ground, but it's much closer to 6 or even a bit over 6. Without leaning it could be well over 7.
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I did a dozen XC trips in one. It burned 5 gallons an hour at 75% power.
 
teejayevans said:
I have 64 gal, the minimum I’ve gotten down to is 20 on a 5.5 hour flight... I don’t know, how wonder how many have run out of gas in their cars?
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Man, when I was younger I ran out of gas in my car all the time. I hate stopping for gas, and love seeing how well I could calculate when the last drop will evaporate in the carburetor. I have witnesses that have seen me run out of gas and coasting up to the pump on multiple occasions. On my motorcycle once I had to push it the last 10 feet....

But I don't get anywhere close in a plane. No way. It's easy for me anyway, my mooney flies far longer than I want to sit still anyway.
 
frfly172 said:
Complacency the more ratings some pilots get,the more complacent they get. It can also be about the money ,trying to stretch to an airport with cheaper fuel.
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SA227 rating. So he was a ameriflight guy?
 
James331 said:
SA227 rating. So he was a ameriflight guy?
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steingar said:
I did a dozen XC trips in one. It burned 5 gallons an hour at 75% power.
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Then you're either a magician or a better pilot than the Cessna factory test pilots, since your fuel consumption is ~20% less than the book figure of 6.1gph.
 
dmspilot said:
Then you're either a magician or a better pilot than the Cessna factory test pilots, since your fuel consumption is ~20% less than the book figure of 6.1gph.
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What if he was flying with a AOA and running LOL after a zoom climb?
 
steingar said:
I did a dozen XC trips in one. It burned 5 gallons an hour at 75% power.
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Picking nits here, but it would be more like ~6 GPH running @ 75% and that’s if you were leaned correctly. Sure you weren’t running at more like 65%?

I fly those little go-karts often, so I’m pretty familiar with their capabilities.
 
Ryanb said:
Picking nits here, but it would be more like ~6 GPH running @ 75% and that’s if you were leaned correctly. Sure you weren’t running at more like 65%?

I fly those little go-karts often, so I’m pretty familiar with their capabilities.
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108hp /2
54lb/hr at 100%
*.65 35.1lb/hr
/ 6lb gal

That's still like 5.85GPH at 65%

Maybe LOP might get you from closer to 6GPH to closer to 5GPH, but with a carb engine and probably no analyzer, guessing we're talking ROP off sound and feel, so I doubt you're going to see better than 6GPH.
 
James331 said:
108hp /2
54lb/hr at 100%
*.65 35.1lb/hr
/ 6lb gal

That's still like 5.85GPH at 65%

Maybe LOP might get your from closer to 6GPH to closer to 5GPH, but with a carb engine and probably no analyzer, guessing we're talking ROP off sound and feel, so I doubt you're going to see better than 6GPH.
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Doesn’t make much of a difference, but the O-200 is 100HP.

I’d say your calculation is just about right on the money. If I recall correctly, the book value does indicate 5.2GPH, but as I’ve said, ~6 to ~6.5 is about the best I’ve ever been able to do and that’s at 75% since nobody is realistically going to be crusing around @ 65%..
 
I have the most imp question that no have asked yet... how do u hold ur bladder for 5 hrs?

Sent from my SM-G935V using Tapatalk
 
It is a discussion that I have all the time with our youth program group. Whenever the topic comes up we talk about the difference between cars (mpg) and planes (gph), why that is and how many stupid pilots manage to kill themselves by forgetting the basics. Apparently once you the plastic in your wallet all those things your learned and had to prove you learned no longer apply.
 
I'm am a complete pu^^^y when it comes to fuel. My personal reserves are 3 hours for a VFR flight and 4.5 hours for an IFR flight.
 
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