If a high percentage of aircraft accidents...

[Scott Philiben]

as long as they are accurate when empty....."what difference does it make?"....

Obviously - that accurate at empty is not what Piper Intended - see post above

 

[wilkersk]

How's that work for you if there's a leak/loose cap/etc? That 13gph you plan for can end up being 7gpm.

Well, then that's called an E-M-E-R-G-E-N-C-Y. And, I'll handle it like any other. If the gauges are rapidly falling, I don't need them to be accurate to tell me I have a problem. I didn't say I never looked at them. Only that I didn't trust them.

 

[Scott Philiben]

Actually the maintenance induced failures combined with simply entering the wrong starting fuel value, makes utilizing the fuel gauge a pretty important component of being a good pilot.

I get the I don't trust - I see this equipment everyday - I wouldn't trust it either

What I want to know is:

• Where did we decide not to require functional gauging.
• When did we decide that adequate performance was the General Aviation accepted norm
• Why didn't we require them to work and function

 

[Checkout_my_Six]

Obviously - that accurate at empty is not what Piper Intended - see post above

but....the only time the fuel gauge "needs" to be accurate is at empty.

 

[Scott Philiben]

No - the silence from the engine lets you know you are at empty

 

[Sundancer]

You keep saying it isn't a high percentage and compared to the other pilot error crashes it isn't. However, my question still stands. Why can't someone come up with a fuel gauge that works all the time, every time?

I think they can - but most of us don't care if they do. My top price would about $79.99.

 

[Scott Philiben]

Histogram of AIDS Fuel Related Accident Data - Events on the bottom X Axis and Pilot cumulative hours on the Y axis

Shows that Fuel Starvation Affects Pilots of all abilities and experience

52% of the above pilots hold a Commercial Ticket

Like I said - It appears nobody is immune

 

[Scott Philiben]

This is what $79.99 gets you

 

[Scott Philiben]

Maybe a fuel gauge like this is required for VFR flight

 

[Scott Philiben]

Maybe this one is a working gauge - He is flying

 

[Scott Philiben]

 

[Sundancer]

This is what $79.99 gets you

I'm good with that. . .

 

[Kritchlow]

...involve fuel starvation, and the only accuracy requirement of a fuel gauge is when it is empty, why can't someone develop a better fuel gauge to tell pilots exactly how much fuel they have left?

I'm not talking about your FADEC stuff, I'm talking about the average Joe flying his Cessna 172 or Cherokee 140 around.

Good.. Because FADEC runs engine parameters, not fuel gauges.

 

[denverpilot]

You want me to tell you how much I'll pay for a product that doesn't exist? It doesn't work that way either.

Works for Icon! ;-) Well, so far anyway... Hahaha.

 

[MauleSkinner]

He said it was a miracle it didn't U port in the pattern. I agree.

Aside from the fact that the fuel level is slightly lower in the pattern than it was one minute before, what would cause it to us port in the pattern when it didn't previously?

 

[EdFred]

Who knew that AIDS caused fuel starvation in planes!

 

[Dan Thomas]

Aside from the fact that the fuel level is slightly lower in the pattern than it was one minute before, what would cause it to us port in the pattern when it didn't previously?

Uncoordinated flight.

 

[MauleSkinner]

Uncoordinated flight.

I would suggest not flying uncoordinated in the pattern so regularly that it becomes the assumption.

 

[Scott Philiben]

I have lot's (More than 100) Garmin G1000 data on moving fuel quantities in the pattern to indicate that flying coordinated is merely a suggestion

The next fuel sender we design will have an alert to tell the pilot to seek further instruction.

Yes Virginia - accurate fuel level has many uses.

 

[exncsurfer]

What about a sensor that weighs the fuel? Does that exist in any design? It could be coupled with a sensor that measures G's. They did put a rover on Mars, this should be do-able.

 

[Dan Thomas]

What about a sensor that weighs the fuel? Does that exist in any design? It could be coupled with a sensor that measures G's. They did put a rover on Mars, this should be do-able.

Someone did come up with a system that sensed the air volume in the tank. Ultrasound, I think. The volume of air will have a resonant frequency that the machine detects, and as the frequency drops, the air volume is increasing and therefore the fuel volume is decreasing.

Its errors would have to do with air temperature. It would need some sort of correction circuitry.

They did put a rover on Mars. It cost how many billions of taxpayer money? Taxpayers have bottomless pockets. Aircraft buyers and owners don't. And since the certification processes are so expensive, we'll be stuck with our old gauges that actually work pretty good if they're all fixed up and kept that way.

 

[Scott Philiben]

The Germans uses a bag under the fuel in WWII aircraft to measure static pressure - It wasn't universally preferred and fell out of favor. A light sport design exists - but I have mixed reviews

Ultrasound failed miserably in aviation - used on early 777 as it could not accurately distinguish fuel vapor boundary and difficulty with fuel movement

There are very simple and effective solutions available - the manufacturers are using them now and they are aircraft grade but not space or transport grade

So you don't have to be stuck - there are solutions

 

[asicer]

What about a sensor that weighs the fuel? Does that exist in any design? It could be coupled with a sensor that measures G's. They did put a rover on Mars, this should be do-able.

Doesn't this essentially operate on the same principle as sight tubes?

 

[denverpilot]

Spacecraft have to deal with ullage.

There's your $0.50 word you'll have to go look up today.

 

[bflynn]

And all this science and technology are short circuited by the nut on the pilot's seat. Ultimately it is still the pilot who makes decisions to or which force him to fly the airplane to fuel exhaustion.

Certainly some of the incidents are mechanical, but much less than 10%. It is pilots who run airplanes out of fuel. Fix that and all the gauges will magically start working.

 

[Scott Philiben]

All the science and technology in automobiles cures the "nut" texting in the lane next to you - automobiles get safer despite the nut in the seat.

Adequate warning of low fuel is mandatory in all forms of fueled transportation technology - failure of this system in all forms is known to lead to fuel starvation

However GA pilots don't believe that this safety analogy applies to this singular form of transportation they enjoy - it is a failure to warn the pilot of bad and very human decisions before they

become incidents or accidents.

This pilot "stupid" thing gets in the way of actually addressing and solving the issue

Aircraft get safer due to technology - TCAS is the shining example of keeping nuts separated

I believe the nut is the pilot that flys with faulty fuel indication - despite it being a regulation

 

[Scott Philiben]

Spacecraft have to deal with balls of fuel floating in space - so ullage takes on a 3 dimensional form

It is my business - so ullage is a next to everyday utilized term

 

[wanttaja]

Ideally, there'd be a "countdown timer" in the airplane that tells you exactly how long the engine will keep running...or even how far you can fly.

Unfortunately, real-world ramifications will tend to nullify any benefit. "It said I had ten minutes of fuel left, and I was fifteen minutes from my destination, so I firewalled the throttle to get there faster."

Also, if the total usable fuel onboard is used for the computation, that time-to-go depends on the pilot switching fuel tanks.

Also depends on the pilot truly, actually, believing the readout. They don't believe the gauges now, why should they trust a fancier gauge unless at least once they run the airplane dry to verify its accuracy?

Finally, as I posted way back in this post, even if it works perfectly, the additional cost and complexity won't have much of a payout. Fuel Exhaustion accidents are much less common than folks seem to think.

Ron Wanttaja

 

[Scott Philiben]

All of this machinations and justifications are to overcome what is a very simple instrument - First you have to have a instrument you trust

OF the now 2100 aircraft outfitted with digital fuel quantity, that is most new delivered aircraft, i.e. Reliable and accurate fuel level indication - Zero have suffered fuel starvation

On the same aircraft with unreliable fuel quantity indication and fuel totalizers the number is 6 starvation events in the same time frame.

According to the several air traffic controllers who approached our booth at OSHKOSH the number of near fuel starvation events are startling

This is opposite of what you are stating - My supposition is that fuel starvation events are under reported due to the stigma associated with running out of fuel

Not all make it to the NTSB report as successful off field landings without significant damage are non-events

If you utilize a simple progression of number of yearly fatalities to the number of incidents and accidents we have 20 to 30 fuel related near misses per week in the USA

This coincides with what pilots other than -" the thought leaders on forums" and the Air traffic controllers approaching the booth or calling us everyday

It happens it is human and there are ways of making it go away.

Beating the dead horse is not one of them

 

[Dan Thomas]

OF the now 2100 aircraft outfitted with digital fuel quantity, that is most new delivered aircraft, i.e. Reliable and accurate fuel level indication - Zero have suffered fuel starvation

Most of the many tens of thousands of airplanes without digital fuel readouts have never suffered fuel starvation.

 

[denverpilot]

Spacecraft have to deal with balls of fuel floating in space - so ullage takes on a 3 dimensional form

It is my business - so ullage is a next to everyday utilized term

Shhhhh. You're a rocket scientist. You were supposed to make them go look it up!

 

[Scott Philiben]

Actually no - that is not true "tens of thousands of aircraft" - where is your proof other than making a bold statement

This becomes circular reasoning - "if only nuts, bad pilots run out of fuel in aircraft"

then it isn't an equipment issue and there would be no difference in two very similar aircraft

Unless your supposition is that only good pilots purchase a particular brand of aircraft

As been pointed out on this forum - Different aircraft suffer different rates of fuel starvation

If that is proven true and there is data to back that up -

it means that bad pilots are somehow attracted to a particular aircraft

I happen to reject the above arguement because it does not hold completely true

Cessna 172 and Piper PA28 have the highest starvation rates - and they are flown by low time pilots

These aircraft also have the highest accident rates overall.

But some aircraft - Cessna 210 suffer an amazing number of starvations


If the starvation rate is consistent with the number of flight hours flown




We know the reported rate of historical incidence and we can infer a near miss rate - for sake of arguement the NTSB incident rate is 10 incidents per million flight hours so near miss events number 10 fold (the simple progression of 10 average deaths to 100 average accidents to 1000 near miss events. all per million flight hours

The AOPA pairs this number down for their NALL report lets just say by half - 5



Because we want to capture the actual issue and the number of real events - so this is 1 in 1,000 hours of flight operation or 1 in 2,000 hrs of flight operation

Even if we use the actual recorded accident number we have 1 in 10,000 hours NTSB and 1 in 20,000 AOPA

Therefore I don't believe your statement about tens of thousands of aircraft as it appears that it is very likely that the aircraft you are flying now, most likely very nearly suffered a fuel starvation event
in it's lifetime. This one is best left to statisticians as it is a role of the dice every year
but for a near miss it is a 1 in 10 chance given approx. 100 hrs flown.

Look around - that means 1 in 10 pilots came close to fuel starvation or suffered an accident

This is consistent to what I hear every day - but again I have a unique perspective and I am not repeating 20 years of magazine, AOPA, FAA reported logic. Logic that I point out above is failed and nobody really wanted to dive deep into the subject.

J. Mac McClellan of Flying Magazine used to put forward a different arguement but it is lost to history.

That present "Pilot Opinion" is consistent with blaming people and not process - if all you do is castigate behaviors - nothing is solved.

 

[wanttaja]

OF the now 2100 aircraft outfitted with digital fuel quantity, that is most new delivered aircraft, i.e. Reliable and accurate fuel level indication - Zero have suffered fuel starvation

On the same aircraft with unreliable fuel quantity indication and fuel totalizers the number is 6 starvation events in the same time frame.

What models of aircraft have the digital fuel quality gauge, and what models of the same aircraft do not?

Ron Wanttaja

 

[wanttaja]

But some aircraft - Cessna 210 suffer an amazing number of starvations.

I've noted that on my own analyses, about twice the rate of other aircraft. I've heard this is due to the complexity of the 210 fuel system; may not be related to gauge accuracy except there not being "total fuel remaining on all tanks" sort of indication.

Help me understand your terminology. When I use "Fuel Exhaustion," I mean the aircraft is completely out of fuel. When I use "Fuel Starvation," the aircraft has fuel, but it was not made available to the aircraft (due to mechanical or human error). Are you using the same definitions?

Ron Wanttaja

 

[denverpilot]

I've noted that on my own analyses, about twice the rate of other aircraft. I've heard this is due to the complexity of the 210 fuel system; may not be related to gauge accuracy except there not being "total fuel remaining on all tanks" sort of indication.

Help me understand your terminology. When I use "Fuel Exhaustion," I mean the aircraft is completely out of fuel. When I use "Fuel Starvation," the aircraft has fuel, but it was not made available to the aircraft (due to mechanical or human error). Are you using the same definitions?

Ron Wanttaja

The 210 anomaly may also be related to primacy. Piper drivers have to manage tanks from day one. Cessna drivers don't have to manage tanks at all until the reach the 210 or one of the Cessna twins.

And lots of people like to stick with bigger types of the same sort of aircraft they flew from the beginning, when they upgrade. Especially if they're not flying for a living, but for their own enjoyment or personal travel. They "step up" to the 210 and bring their 172/182 habits with them.

 

[Dan Thomas]

The 210 has very little wing dihedral, and when the fuel is low it unports easily. Cessna has POH amendments and service letters warning of this. It has nothing to do with fuel gauges. It has everything to do with knowing the airplane's limitations.

 

[Dan Thomas]

Actually no - that is not true "tens of thousands of aircraft" - where is your proof other than making a bold statement

This becomes circular reasoning - "if only nuts, bad pilots run out of fuel in aircraft"

then it isn't an equipment issue and there would be no difference in two very similar aircraft

Unless your supposition is that only good pilots purchase a particular brand of aircraft

As been pointed out on this forum - Different aircraft suffer different rates of fuel starvation

If tens of thousands of airplane ran out of fuel, we'd have a lot fewer airplanes in the fleet than we do. Fuel exhaustion accidents tend to destroy the airplane and sometimes the occupants. As Wanttaja says, fuel exhaustion is a tiny factor compared to loss of control of the airplane when it comes to causes of accidents.

Maybe Wanttaja could tell us what percentage of various models are still in service. It would be interesting to know how many Cessna 172s, of all those built, are still flying.

 

[wanttaja]

If tens of thousands of airplane ran out of fuel, we'd have a lot fewer airplanes in the fleet than we do. Fuel exhaustion accidents tend to destroy the airplane and sometimes the occupants. As Wanttaja says, fuel exhaustion is a tiny factor compared to loss of control of the airplane when it comes to causes of accidents..

Actually, IIRC, the fatality rate for fuel exhaustion accidents is kinda low. All they have to do is land, the same thing they do after every flight. It's just no longer at the pilot's discretion.....

Maybe Wanttaja could tell us what percentage of various models are still in service. It would be interesting to know how many Cessna 172s, of all those built, are still flying.

No one can tell you how many are flying. But a comparison with the Deregistered list might be able to give us some bit of insight.

I'll do some digging on both items this evening, and post any findings.

Ron Wanttaja

 

[Scott Philiben]

I agree with denverpilot - feeding tanks from both addresses a lot of issues. However both tanks don't drain at the same rate and you always have to draw from one or the other to stay balanced. You actually know this when you have accurate fuel gauging. Somebody suggested coriolis effect - I suggested aircraft trim and rig

Beech Bonanzas also suffer a higher rate of fuel incidents, they also have unporting issues - hence the 12 gallon yellow arc added when new or by service bulletin (I don't remember if this was also an AD)

Some aircraft you can see all the fuel, and in a hershey wing PIPER you should be hard pressed not to know your starting fuel - but in some aircraft you can't. (Baron's, Bonanza's, Cirri..etc)

But I have a lot of Piper loss of power incidents that are - No Faults Found and fuel incidents where there should have been fuel but nobody bothered to look where it might have gone - with fuel gauging we would have a better picture of what is causing these issues. (Reference - NTSB Database - Search TERM "Loss of Power")

In the "can't" camp are a lot of small business jets and turboprops which to compensate for this and to meet pilot expectation have traditionally better fuel quantity information -

Funny thing is, with better fuel quantity information the fuel starvation statistic for this class of aircraft falls to near zero.

Professional and ATP pilots make up 44% of the fuel starvation statistic in GA - something they find very difficult to do in more sophisticated aircraft.

But this is a pilot problem, because there are official FAA pamphlets stating it to be so - I don't think so, and like most here, the FAA is not my particular paradigm of virtue

I guarantee Dan that you have GPS in your aircraft, because it is better than LORAN and better than dead reckoning. Pilots of all abilities navigate better with GPS - we all agree that to be true.

By your responses, you appear to want to cling to antiquated, corroded and non functional required fuel quantity instrumentation because it is a pilot badge of honor to do so

And for the life of me - I have no idea why

 

[Dan Thomas]

I guarantee Dan that you have GPS in your aircraft, because it is better than LORAN and better than dead reckoning. Pilots of all abilities navigate better with GPS - we all agree that to be true.

By your responses, you appear to want to cling to antiquated, corroded and non functional required fuel quantity instrumentation because it is a pilot badge of honor to do so

And for the life of me - I have no idea why

I would like to see better fuel gauges, but they still won't prevent fuel exhaustion. That's my point. There are far too many examples of guys pushing on when they could have stopped for fuel but didn't, and they knew they were low on fuel. I used to be a flight instructor and had plenty of opportunity to read accident reports. We could only shake our heads with some of those events. The same thing goes for a lot of other stuff, like carb ice. By some estimates, carb ice is the biggest single cause of engine failure, even more than fuel exhaustion. It comes down to training and the willingness of students to learn some things.

I work on aircraft all day now, being an aircraft maintenance engineer, and deal with fuel gauges and gauge calibrations among many other things. I'm the guy that points out the shortcomings and failure modes of those float-driven rheostats. I'm also the guy that points out that fuel gauges must be there and they must be working. Go back to post #9.

But when so many guys can barely afford to fly, they aren't about to spend several grand on new gauges that work better. And I don't find corrosion on fuel senders any issue at all, either. They just wear out that rheostat, or the float develops a leak and sinks. Some of the gauge systems I see on certified aircraft are simple but also dangerous, like the clear plastic gauge tubes on some bush-type high-wing airplanes. I have found those cracking from the inside out, and if one failed in flight you'd be almost guaranteed an accident, maybe an inflight fire, and probable starvation since these systems are typically plumbed together with an on-off valve. All that fuel would drain into the cabin. Fun, huh? Many old airplanes had better gauges in the wing roots than that: They had mechanical gauges that sometimes had a magnet inside the tank and a needle outside it that followed the magnet. Nothing much to go wrong there. Even a broken glass face wouldn't leak the fuel. Is everything new really better? Not all of it.

What bugs me is that owners sometimes expect 50-year-old gauges to keep working. Another thing that bugs me is the silly cost of replacing antiquated systems, like those gauges, when homebuilders can do it cheaply.