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Showing posts with label fuel quantity indication. Show all posts
Showing posts with label fuel quantity indication. Show all posts

Sunday, August 17, 2014

Fuel Gauges: Do they Indicate Properly


Fuel Gauges: Do they Indicate Properly?

by Tom Bennett, Civil Aviation Safety Inspector, Aircraft Maintenance and Manufacturing, Prairie and Northern Region, Civil Aviation, Transport Canada
There have been multiple incidents of fuel exhaustion over the past few years. In the last issue of the Aviation Safety Letter (ASL), you read about fuel starvation due to improper fuel selector condition. In this article, I would like to talk about another common factor in fuel starvation incidents: fuel gauges that do not indicate properly.
Some incidents were very public, whereas most incidents went unnoticed with the exception of being listed in the Civil Aviation Daily Occurrence Reporting System (CADORS). Some incidents were directly related to poor fuel management by the flight crew(s); however a few came as a surprise to the flight crew, as the fuel gauge(s) still indicated there was fuel in the tanks. An accurate reading of the fuel gauge may have prevented many of these occurrences.
There is some confusion about the need for serviceable fuel gauges. This confusion is especially prominent in the general aviation world. As both an aircraft maintenance and manufacturing inspector and an enforcement investigator, I have heard statements like: “The gauges have never worked properly. I just keep track of time in my tanks,” many times.
Such a statement is contrary to Canadian Aviation Regulation (CAR) 605.14(j)(i), which states: “No person shall conduct a take-off in a power-driven aircraft for the purpose of a day VFR flight unless it is equipped with a means for the flight crew, when seated at the flight controls to determine the fuel quantity in each main fuel tank […]”. This regulation is then carried through in sections 605.14, 605.15, 605.16 and 605.18 of the CARs, to apply to all power-driven aircraft in all nature of flights (day/night visual flight rules [VFR]/instrument flight rules [IFR]).
Furthermore, many aircraft must have their fuel gauges working as per their type certificates. For larger aircraft, especially transport category aircraft, the fuel gauges can be deferred by means of the minimum equipment list; however, this usually involves using other measuring devices installed on the aircraft and making complex calculations.

Fuel Gauges that indicate incorrect fuel levels
A common factor in fuel starvation incidents:
fuel gauges that do not indicate properly

Recently, a commercial pilot was fined because one of his fuel gauges was not working while he was operating an aircraft. In this case, as in others, the fuel exhaustion caused substantial damage to the aircraft during the forced landing. The pilot applied to the Transportation Appeal Tribunal of Canada (TATC) to seek relief from the $750. The TATC upheld the Minister’s decision.
The Aviation Enforcement Branch has also sanctioned aircraft owners and operators for unserviceable fuel gauges found during Transport Canada’s oversight activities. The maximum sanctions for an infraction under CAR 605.14, 605.15, and 605.16 are $3,000 for an individual and $15,000 for a corporation. The maximum sanctions for an infraction under CAR 605.18 (IFR) is $5,000 for an individual and $25,000 for a corporation. Inspection, maintenance and repair of a fuel indication system seem less costly, in my opinion.
Another common excuse I hear is that the gauges have always displayed faulty readings or they are too difficult or expensive to calibrate. As an aircraft owner, if you rely on this flawed thinking you are exposing yourself to numerous risks. First and foremost, you risk running out of fuel. This can lead to personal injury/fatality and damage/loss to the aircraft. Second, you are exposed to regulatory action by enforcement (fine or suspension). I think we can all agree that none of these are pleasant outcomes.
For the aircraft maintenance engineers (AME) in this scenario, I have not yet seen an inspection where the functionality of the fuel quantity indication system is not checked. Be careful what you sign for on the inspection forms and subsequently, the maintenance release. Following manufacturers’ instructions for inspection, maintenance and repairs will never lead you astray.
Most pilots and AMEs are aware that any accident or incident results from a series of events; there is never just one cause. Anything we can to do tighten up against the possibility of an error is a step in the right direction. 


Crown Copyright and Licensing, Public Works and Government Services Canada
Crown Copyright Clearance CCL FILE # 2011-33369
(c)Transport Canada, Aviation Safety Letter Issue 1/2011

Thursday, March 20, 2014

Measuring Fuel ... How Do you Measure Up?

I have been trying to track down this exact "Pilot Folklore" regarding fuel level in aircraft.
  
Specifically the widespread pilot belief that the FAA doesn't require for you to have working fuel gauges in your aircraft.

The gauges only need to tell you when you're empty.

Sure enough in a FAA Safety Bulletin in April 2002
The FAA said just that - the exact words as follows:
 As you can see, the regulations only require that the aircraft fuel gauge read “zero” during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply determined under 14 CFR §23.959(a).  Therefore, the gauge cannot be depended upon for checking the fuel quantity in a tank. This is especially true of the smaller, less sophisticated general aviation aircraft. Visual or physical checking or both are the only safe means of determining the actual quantity of fuel onboard such aircraft. How do you measure fuel? Do you measure up?  H. Dean Chamberlain 
In fact,  as recently as February 2013, the FAA allowed this to be reprinted in a blog site... unbelievable.   Supporting a culture where it is acceptable for "Fuel Exhaustion" to be one of the TOP 5 GA Incidents, and according to the AOPA Nall Report the second highest cause of pilot death.

In most cases pilots will blame  pilot behavior and preflight.  All pilots will rally to the aviator cause, and like this FAA article, seek to change the an obviously errant pilot procedure.   .... Education is the tool to address this serious safety issue .  Despite the efforts, the number of fuel exhaustion incidents still remain high.
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So back to the fuel gauge ....  I have been through over 150 certification meetings in my life - 

But I have not yet brought in a new aircraft or new aircraft modification and told the Administrator that; 

I removed the fuel gauge and  replaced it with an idiot light letting the pilot know -

"That at this very moment you ran out of fuel"  

or propose an aural announcement like:

 "WARNING YOUR ENGINE WILL NOW STOP... PLEASE LOOK FOR A SAFE LANDING & HAVE A NICE DAY"

But according to the FAA author above - that is exactly what the administrator is looking for in an aircraft design  ....

...   REALLY,  What pilot or aviation professional believes this?


 So what do the FAR's (Federal Airworthiness Requirements) really say:
Title  14 Code of Federal Regulations (CFR) §23.1337(b), Powerplant instruments installation.
  It reads:
(b) Fuel quantity indication. There must be a means to indicate to the flightcrew members the quantity of usable fuel in each tank during flight. An indicator calibrated in appropriate units and clearly marked to indicate those units must be used.
It says you have to have a fuel gauge and it needs to show you the amount of fuel in your tank in flight.  It says that in fairly clear language. 
In  addition:  
(1) Each fuel quantity indicator must be calibrated to read “zero” during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply determined under 14 CFR §23.959(a);
It says that the fuel gauge must have the capability to be be calibrated to read zero usable fuel.  This feature is an added part (In addition) to the requirement that it must  let you know how much fuel you had in total,  when the aircraft is in flight.

Does anyone believe that the FAA would have you put a fuel gauge in an aircraft and 
let that gauge

  • Indicate any value fuel level other than zero.
  • When you were at zero usable fuel it will read "ZERO"
According to this skewed interpretation of the regulation.

A binary gauge meets this folklore requirement   ... 

  •  "SOME FUEL"
to be followed by a calibrated  
  • "NO FUEL" 


Well the FAA actually expects something dramatically MORE Accurate 

in FAA TSO C55a -

- No more than 3% of full scale tank volume in the worst case -

Minimum Performance Standard for Fuel and Oil Quantity Indicating System Components




When you get in your aircraft and you look at your fuel gauges.

  • Do they meet the real and intended FAA standard. 

or 
  • Do they just give you folklore.



Sunday, May 12, 2013

CiES Inc Update

If we reflect on the past year we have accomplished quite a bit

  • Secured a OEM contract on the most produced General Aviation Aircraft  - Cirrus SR20 & SR22.
  • Obtained a TSO for producing this fuel level sender applicable to all aircraft.
  • Received retrofit approval to install our TSO sender on all legacy Cirrus Aircraft. 
  • Designed an LPG (propane) level sensor with iPhone/iPad interface
  • Initiated OEM installation on the Gippsland GA-10 Turboprop, Discovery 201 & Vulcanair P68 Aircraft series.

  • Achieved aircraft industry recognition for our accomplishments
What is now happening behind the scenes is truly impressive 
  • Engaged in engineering design with several manufacturers for installation of our fuel level sensors on their aircraft platforms.
  • Working three new aircraft platforms 
  • Involved in several STC retrofit applications 
  • Finalizing the boat level sensor to display at a major customer
  • Engineering new aircraft systems and interfaces using our technology
  • Planning for exposure in non aviation markets 
So we have been quite busy and very active - and look forward to next opportunity to demonstrate our capabilities