Britten-Norman Islander Fuel Quantity Senders

Britten-Norman Islander Fuel Quantity Senders  

We just completed a set of Britten-Norman Islander senders for the manufacturer.   

We placed the old Britten-Norman sender design alongside the CiES design for contrast.  Like a lot of small aircraft manufacturers, Britten-Norman had to modify commercial resistance senders to work in their application until we came along.

If you look closely you will see the careful welds on the legacy sender float arm and if you look inside you will see tank sealant applied to the riveted and electrical connections to prevent fuel leakage through the sender body.

The CiES fuel level sender is built for the application, with a custom arm dedicated to this assembly.  Our non contact fuel quantity measurement insures that leakage will not happen through the sender body.  

All of our sensor electronics are fully enclosed in the aluminum housing.  Unlike traditional failure prone senders - our senders have amassed an impressive record of 300,000 hrs of flight time without error or in service replacement.   We will change your opinion of what float fuel senders are capable of - both from a precision and reliability standpoint.

Finally a fuel level sender designed for the aviation market.

CiES Mooney Fuel Level Senders - A Digital Fuel Sensor with Analog Outputs

Today we delivered 2 sets of CiES Mooney Fuel level senders for late mode M, R, S, & TN Mooney aircraft.

So we now have fuel level senders for the popular Mooney Bravo, Ovation, Eagle & Acclaim. 

We are now adding a new aftermarket general aviation platform every week.  

In addition CiES is adding a new OEM or commercial application every month.


Unique to CiES Fuel Level Senders:

• Set 1 - was set up for a Mooney Bravo with a voltage output for interfacing to a JPI 900 
• Set 2 - was set up for a Mooney Acclaim with a resistive output for the factory G1000 system.

CiES has the unique capability of supporting multiple platforms with the same sender design.  This sender design physically plugs into the same mounts in the aircraft.

While the float remains - CiES's method of measurement is lightyears away from the traditional potentiometer or resistive sender of the past.   CiES senders utilize a patented magnetic field technology that has more in common with the digital compass in your flight instrument or your cellphone.

Like a compass that always points north, the CiES fuel level sender always points to the float.  The sensor is precise enough to measure the angular position of that float down to tenth's of a degree and that precision is repeatable over time, temperature and vibration. 

Magnetic Field Fuel Level Senders - Resistance Output

 Another Day And Another New Fuel Level Sender Configuration @ CiES 

While we discussed the Universal Output Sender in a previous blog post, it's much better to talk about an actual fuel level sender we are sending off to it's intended OEM manufacturer.   

This new configuration will output an equivalent resistance to be read by a gauge or the aircraft MFD.   While it appears on the surface to be easy it is actually the result of a 3 year effort to provide an output suitable for the aviation environment.   

Our senders are natively frequency output based, and this output has proven to work very well in our OEM and retrofit applications for Cirrus Aircraft,  but what we needed to do was convert that frequency to either a voltage or resistance output.

So we manipulate this native output to provide a variable voltage or a variable resistance.  

This unit for a new customer contains everything we wanted to provide;

• Frequency Output Fuel Level
• Slave Sender Input
• Resistance Output Fuel Level
• Fuel Temperature 

It is the culmination of making a Fuel Sensor that is compatible with most platforms out on aircraft & helicopter platforms in the field.

Cessna Cardinal 177 Fuel Sender Design Process

Can we offer a Retrofit CiES Fuel Sender for your aircraft. 

What are the steps we need to take: 

New Cessna 177 Cardinal Fuel Level Sensors 

• Obtain a a set of old fuel level sensors from the aircraft we are considering.  If the part numbers for the senders match the aircraft they are on, we are good to go.

• Ideally this aircraft should have a strong user base with an owner base that demonstrates their willingness to embrace new technology with their pocketbook.

• Discuss the compatibility with commonly installed MFD components or instruments.  CiES  Fuel Level Senders now has the capability of driving even old analog gauges in the aircraft (Universal Fuel Level)..

• Our market is the pilot / customer that is more concerned with fuel level issues and wants the required fuel level instrument in the panel to have the  capability of multiple point calibration.

Old Cessna 177 Stewart Warner and Leigh Fuel Sensors 

• Evaluate the existing sensor design -  For example the bends in these sensor arms are either to assist in installation and removal of the fuel sensor or to clear aircraft structure in the fuel tank.

• As our sensor design allows for an easily detachable arm - these bends might not be necessary and simplify the design greatly.

• We then proceed to manufacture a prototype sensor with our best guess for geometry.

Cessna 177 Cardinal Fuel Tank - Internal Shot

• Check the sensor in the aircraft fuel tank.  As you can see in the illustration - in this case the simple arm design works better in the tank and sweeps a better fuel volume being closes to the Spar and maximum chord point.

• At this point we qualify the design with drawings and procedures for the completed unit so that we can send these files to the FAA to have this configuration added to our TSO.

Fuel Tank with Prototype Sensor Installed 

• Once we have approved drawings we can can produce the required sender with a TSO Tag attached.

• The fuel tank is then drained, the aircraft leveled and braced only then is the zero fuel amount added.  There should be movement of the sender to be able to record an accurate zero fuel level, this is an absolute requirement.

• Fuel is then added to the tank incrementally and accurately to obtain data points for calibration.  We direct the installer to take special caution to insure tabs fuel value is accurately recorded by the fuel display.

• Equally the installer needs to insure full fuel level per the POH is also accurately displayed.   

Note:  All aircraft fuel tanks are built with expansion volume - Full fuel per the POH may or may not be to the neck on the filler plate.  This is very important as the aircraft will probably be fueled in the future on a ramp -

Varying fuel tank angles caused by imbalanced fuel filling - filling one side before the other

or 

The angle of the ramp typically created to drain water from the ramp surface.

Both of the above have an effect on apparent aircraft fuel level from simple visual observation.  

• A confirmation of entered fuel level and actual fuel level when the aircraft is in stable cruise flight may allow the pilot to correct for an erroneous starting fuel level value. 

• The final result is a happy customer with a new fuel sender design that has hundreds of data points to describe the fuel tank contents on their new MFD display or instrument.

Note:  While this seems to be an involved procedure - accurate fuel display on an aircraft requires this level of detail otherwise you might not get the information you need.

Tilting @ Propellers

Illus. Chris Demerest http://chrisdemarest.net 

Today I took a call,  the pilot on the line was enthused, he really wanted to get our new technology fuel senders on his aircraft.  

Further he engaged us in a dialogue wanting to let us know how significant this product was to aviation, and to his passion, you know the type,  a typical Mooney pilot.

He told me about the AOPA statistics on fuel mismanagement and starvation, and that it wasn't good press for general aviation or general aviation safety  to have a fuel starved aircraft parked along  a busy highway.

He was adamant to tell us about the significance of redundant and confirming cockpit information.  Being able to cross-check the two independent fuel quantity indications in his cockpit, he felt, would virtually eliminate fuel starvation in general aviation aircraft.

He talked about the level of quality he saw in fuel senders used in aviation, and that he just hoped he wouldn't have to overhaul his original set for the umpteenth time, and then have them fail hours later in flight, as they had on the past two occasions.

He related to me that as a multi type rated and experienced pilot he had never flown behind a good aviation fuel gauge in his entire life.

I didn't say a word  I sat back and listened to the sentiment that put us on the path to start a company around this product and idea.

The idea that we will build a good fuel level sensor, a quality fuel level sensor,  around robust patented technology using aerospace materials and standards.   We will prove our commitment by qualifying this fuel sensor to the most ridgid FAA standards for manufacturing and design.

My dream is that pilots will get this and install or demand this technology on their aircraft.  If that happens, we will make a lasting contribution to the aviation industry.

So many times in this aviation business,  you feel like you are setting your train along the wrong track,  why are you building a company in aviation,  when successful people all around you question the market size, vitality and rational.   You question your own sanity on a daily basis.

I guess we do this,  because our passion makes us tilt toward that propeller.  some days it's nice to know we aren't the only ones.

Aircraft Fuel Totalizers - A Self Fuel Filling Prophesy

One of the more difficult things to measure is liquid fuel on a moving vehicle.  

This is true of aircraft, boats and heavy equipment.  

By it's very nature, liquid fuel refuses to stay still.

So to address these issues with fuel level sending technology,  we have turned to fuel flow instruments and fuel totalizers.  

These instruments measure the fuel flow to the engine and remove that fuel volume from an owner/operator entered starting fuel value.  They can give you a  knots per gallon indication. 

This can be done by several methods - we can count injection pulses and duration or we can get a sensor to measure fuel on the way to the engine,  and in injected engines fuel on the way back to the tank.   There are several sensor types that will perform this function

Some of our cars do the same thing - only they reset when we fill the tank or in other words when the fuel level reaches full.

---------------------------

Many owners will swear by the fuel totalizer and it's uncanny accuracy.

I filled the tank and then burned 35 gallons of fuel.   When I refilled - I put 35 gallons back into the tank.  

Sounds good - and a justification for the expense of having this equipment installed - However an aircraft tank filled in the same manner and in the same location - the fuel totalizer is a self - fuel filling device.

• I will never run out of fuel with this equipment installed.

• I don't need fuel gauges 

---------------------------

So what does the FAA say about fuel totalizers 

Digital fuel flow computer systems have a fuel flow transducer that directly measures the fuel being fed to the engine.

The fuel flow transducer may be a small paddle wheel, an impeller, or spring-loaded movable vanes. 

Digital displays with a fuel computer also allow these instruments to display total fuel consumed, total fuel remaining, and time remaining at the present fuel
flow rate for fuel management. Overall accuracy for fuel remaining and time
remaining readings depends on the transducer processing unit and display.

The largest possible error is the initial fuel supply, which is entered by the pilot at the start of each flight. Errors in the initial fuel supply may be caused
by an uneven ramp, unusual loading, volume changes of the fuel because of
temperature variations, malfunctions in the fuel system such as leaks,
siphoning actions, collapsed bladders, and other factors.

So, total fuel remaining should be verified with the fuel quantity indicator. According to § 23.1337(b)(1), fuel quantity indicators are required to be calibrated to read "zero" during level flight when the quantity of fuel remaining in the tank is equal to the unusable fuel supply. Therefore, fuel quantity indicators should be used as the primary fuel-remaining instruments.

Fuel quantity indicators that are inaccurate should be periodically calibrated, repaired, or replaced, as necessary, to ensure reliable readings.  

Taken from  FAA AC 23-17C

-------------------------------------------------------------

The only issue with the FAA message above is that it was written for aircraft engineers, certifying new aircraft or modifications -  

It really should be shared with the pilot and aviation maintenance community.   

Why not?

-------------------------------------- 

Fuel Starvation in a Modern Technologically Advanced Aircraft.

It is common to believe that technological advances can mitigate the dangers inherent in operating vehicles.  The automobile airbag is one of the best examples - it was first hard to convince us all we needed one - now every new car has 10's of them.  It was a safety idea that worked.   

One of the most difficult Safety Issues in Aviation - Especially light aircraft is Fuel Exhaustion. 

And we have a strong belief that modern aircraft with modern tools can mitigate this problem.  

There is a definite trust in the pilot community that fuel totalizers (fuel range calculators) mitigate the danger inherent in running out of fuel in a small aircraft.   This is the technological advance intended to help alleviate fuel starvation events for small aircraft.   For those not in the aviation field - you are guessing correctly that running out of fuel in a small aircraft is not a good thing. 

So lets look at a recent Fuel Starvation event in a modern Cirrus SR20.  

The National Transportation Safety Board provides a Probable Cause for this accident that occurred in Parker AZ - 

I included it below -

Before the first flight of the day, the pilot visually checked the airplane’s fuel quantity through the fuel tank filler necks, observing what he believed to be full tanks.  He subsequently checked the fuel gauges, which indicated that both wing tanks were less than half full.  Surmising that the gauges were faulty, the pilot departed on a short flight to a local airport to pick up a passenger.  After picking up the passenger, they departed for a cross-country flight.

So this subject pilot observed full tanks (he actually looked at the fuel in the tank),  and then checked to see what his gauges read.  Then this Cirrus pilot with an "obvious" discrepancy between his observed fuel and his fuel gauge reading,  proceeded on his planned cross-country trip.   

It is my conjecture that he entered full fuel on his fuel totalizer.  The totalizer is a system that uses fuel flow and a pilot entered quantity to provide a range of travel.  Systems like this are common in boating and you see them in your car as a fuel range.   So this pilots "trusted" fuel reporting system supported his  observation.   

This pilot then departed with in his words "faulty gauges"  - and in violation of Federal Law Title 14,  Part 91 -  included below:

§91.7   Civil aircraft airworthiness.
(a) No person may operate a civil aircraft unless it is in an airworthy condition.
(b) The pilot in command of a civil aircraft is responsible for determining whether that aircraft is in condition for safe flight.  The pilot in command shall discontinue the flight when unairworthy mechanical, electrical, or structural conditions occur.

So this pilot operated his aircraft with with an un-airworthy mechanical condition based on his observation of fuel level.  

In fact if you ask a pilot friend if they are currently flying an aircraft with a faulty fuel gauge you will get a nearly unanimous answer that yes in fact they are.

Typically they will soften the blow and let you know, 

• That they have never run out of fuel.
• They can look in their fuel tanks on the ground to see how much fuel they have. 
• They will tell you that a stopwatch will let them know when to land.
• And aircraft typically are operated at one speed - so fuel consumption per hour is fixed.  I have 50 gallons of fuel - we burn 10 gallons an hour - so we can go 5 hours maximum - and today we will only fly 3 hours.
• Some will even tell you that they have a Totalizer - and it's far more accurate than any fuel gauge 

As you can correctly guess - this law, the one that requires working fuel gauges in aircraft, is not enforced.  Nobody is getting busted, and frankly nobody is worried about it either.    

But this pilot didn't break the law -  the fuel gauges were right and his aircraft was in the legal words of the law - airworthy -    The only thing this pilot did was err in his observation of the fuel level in the tank.   Human error it happens all the time  

So a little more conjecture based on what we know of the Cirrus SR20 aircraft   -  This pilot in believing his gauges to be wrong,  he then ignored the the multiple low fuel level messages that occurred during flight.   You could think of these aircraft warnings as a low fuel warning lights - that first come up amber and then change to red as the fuel is being depleted out of the tank.

These low fuel messages were warning him of an impending fuel emergency,  most likely where he could have taken action and landed safely.   But this pilot appeared to have trusted his  "Fuel Range Map -  and his fuel range on that map was based on his erroneous fuel level observation and his range map was counting down from a full tank of fuel.   He might even have carried a stopwatch to let him know at what time he would have run out of fuel.

This is the cultural issue in aviation  - 

• Pilots find it acceptable,  actually common to fly with a faulty fuel gauge.
• Pilots expect that the fuel gauge is misleading and proceed to fly anyway.
• Pilots were trained to ignore their fuel gauge   
• Pilots continue to run out of fuel in their aircraft 

If this pilot trusted his fuel gauge - and then used it as a cross check to his fuel level observation - he would have exited the aircraft on the ground  and re open the fuel tank and reviewed his observation.   In fact as he made a short hop to pick up a passenger -  he could have rechecked the fuel level twice.   If I we use this aircraft's  Pilot Handbook Checklist - a visual tool that pilots use to insure everything is working as it should,  prior to flying - he would have looked at his fuel gauges a minimum of 10 times,  and he then ignored his fuel gauges each and every time.

Fuel Starvation - or running out of fuel is a leading cause of aircraft accident, injury and death.

So what are the FAA, NTSB and the Pilot Organizations doing about this -  

Well, not surprisingly

  They too want to ignore the fuel gauge.

Again nearly all pilots were trained to do so.

In the most recent video & safety bulletin put out by AOPA and a they have placed a lot of effort to train this pilot to visually observe the fuel in his tank. 
Pilots, due to the cultural influence can't grasp the idea that a working fuel gauge could possibly mitigate fuel starvation.
  
It never occurs to them.

And it is really is a head in the sand approach,  As these pilots are all cross checking each other, and sharing their own experience.   

Just like the airbag, we were resistant to add safety, as it added cost, and we doubted the benefit - but the value of the lives it as saved has made it more than worth it.  

-------------------

Let's change the culture in aviation and quit making excuses and ignoring equipment that doesn't perform to the aviation standard .

Universal Fuel Level

Universal Fuel Sender

When we started out to re-define fuel level in aviation we looked at every aspect of what was causing present sender systems to fail.

We then broke that down into three basic concepts that needed to be addressed:

1. The sending unit had to accurately report the position of the float in the fuel tank.
• We used our Patented AMR Sensor Solution
• Exceptional Accuracy
• High Reliability
• Non Contact  - Fuel or liquid intolerant 
2. The sending unit had to be built to aviation standards.
• We utilized aerospace materials and tight tolerance machined parts
• Aerospace Coatings
• TSO Designation - built and tested to an Aerospace Performance standard
3. The communication to the cockpit of the fuel level had to be fool proof
• We used a digital frequency output
• Easy communication, no connection or wiring issues
• Similar communication to fuel flow
• Easy to diagnose 

We created a phenomenal solution for aviation - In 1 1/2 years of delivering this product - we have yet to have an unscheduled removal from an aircraft - 

Over 2500 units in the field and not one failure.  

We produce this unit for the highest production single engine aircraft.

We measure Avgas, Jet A and Alcohol De-Ice fluid with the same unit.

We addressed the aviation aftermarket with a display partner Aerospace Logic to produce an  fuel level display unit that would accept our frequency input.    Aerospace Logic has approvals for their display in all types of GA Aircraft.

We addressed and solved a perplexing problem in aviation

 Accurate and Reliable Fuel Level

In creating news in the aviation field  we have generated a lot of  interest in our product. 

Fuel Sending Units are Universal 

Applicable to all fuel tanks

in any industry or vehicle 

same SAE Bolt pattern 

We are expanding our market 

The new sending unit design needs to have optional outputs:

1. Digital Frequency - proven in the field - exceptional clarity
2. Ratiometric Voltage - a  0 to 5 Volt solution
3. Current Output - simulating a variable resistance  

With this configuration we can accommodate all cockpit or instrument interfaces  - we even left a pigtail to accommodate existing connectors 

Talk to us about any fuel level sending issue 

Cirrus Aircraft Factory Fuel Level

We have been supplying Cirrus Aircraft fuel level senders for over a year.  There have been no issues or in-field replacements.  Now that the senders have proven themselves day in and day out and showing excellent reliability and repeatability.  We can now start to exploit the advantages accurate fuel level can provide.   

In the Cirrus Aircraft Facebook post yesterday - one of these new features came to light.  

Cirrus wrote the following:

Since spring of last year, our aircraft have come equipped with fuel level sensors that read accurately at all levels. In fact, they are so accurate that we were able to integrate a fuel imbalance message on the PFD in Generation 5 aircraft. The fuel level sensors in most of our competitors’ planes only read accurately when the fuel tank is empty or full. For more on the astonishing innovations that make Cirrus an industry leader: 
http://bit.ly/YZO6rT

Better information =  "informed"  decisions

As always when you forget,  a careful reminder will get things back to normal

In Memoriam - Charles W Beck

Charles Wesley Beck II.,Born in Fort Worth, Texas on June 26, 1933, and passed away on December 19, 2012. 

In 1975 he founded International Avionics, a position he held until his death. The company is a supplier of annunciator systems and control electronics to the general aviation industry, both original equipment manufacturers and aftermarket completion centers.

Charles was dedicated to the design and manufacture of products that improved the safety and operation of aircraft.

The Mooney Aircraft Master Annunciator was one of those projects.

Charles designed and patented the AMR fuel sensor concept owned and utilized by CIES Inc.

We are proud to carry on his legacy in providing accurate and reliable fuel senders to the aviation market.

Digital Fuel Sender Now Certified

Digital fuel sender now certified

The AOPA Press Release came out today
It seems to be difficult to find, but it is on the web

The basic concept is ....


When we have specific aircraft (or aircraft type) information
and we demonstrate that the system is compatible to Transport Canada ... Flight Test
or operation under 337 Field Approval

We can add those aircraft onto the blanket AML STC owned by Aerospace Logic.

We believe after we demonstrate on several aircraft types that this is simple modification and installations are straight forward  additional aircraft models will fall into place.