Cessna - Friggin Lasers in Their Fuel Tank

Hidden Costs Behind the High Cost of Aviation 

I had started to re-energize our 2015 marketing effort  and wrote a few blog posts about delivering magnetic field fuel senders to,  new to us,  European Aircraft and Helicopter customers.  We seem to be popular over there,  we may owe many thanks to Flieger editor Thomas Borchert  

To check on our progress on our google search listing placement,  I ran across a G1000 Cessna Fuel Sender for Sale on Ebay  and thought I'd share it.

This is a Meggitt TDR (Time Domain Reflectometry) Fuel Level Sensor for a Cessna Single Engine.

• Used Ebay Price is $1,800 each
• New Price from large Cessna Parts Jobber is $3,100
• Cessna List Price is $3,864.  

The Meggitt Fuel Level Sensors do look well made and come with a nice calibration sheet for your Cessna 172, 182 or 206.

Replacement Cost for 2 of these sensors on a Cessna would be $7K to $8K a Kit -  Installed cost would be well over $10,000 - This for a retrofit fuel level system on a Cessna 172 for heavens sake.  It is painfully obvious why there isn't a retrofit STC available.

Maybe some in aviation are correct,  airplanes are getting to be very expensive  - part prices contributing greatly.  But with a bit of creativity, it doesn't have to be.   

The caveat is,  that our Fuel Level Sensors met all the FAA TSO requirements that the TDR fuel sensor has met - and we do it for far less money.  I was told early on,  Engineering is not building the best without regard to cost, it is providing best performance at a price that is attractive to your consumer and the FAA.   

While I have heard that our FAA TSO fuel level sensors are expensive compared to legacy commercial grade resistance fuel senders, i.e. the kind of sensor they used to put in aircraft of the past.   I agree to a point on the expensive part arguement, but I truly feel CiES hit the target.  We provide improved aviation technology and performance at a competitive price. 

This Meggitt TDR sensor is not a well known change to the venerable Cessna Single Engine Lineup,  you would be hard pressed to know this was in your wing unless you queried the Cessna Illustrated Parts Catalogue.   There is no mention of this system any Cessna Marketing literature.   You'd think that a $8,000 fuel level system would be worthy of editorial or marketing content  - I guess it isn't.

Almost overnight the world of aviation fuel level changed and somehow nobody bothered to notice.

The TDR system works by shining laser light down a glass rod and measuring returns, so next time you come in contact with a G1000 Cessna owner - Let them know they have "friggin" lasers in their fuel tanks. I am going to bet they'll be surprised.

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.

Cessna Cardinal 177 & 177 RG Fuel Level Sensor

Well we produced another configuration of our fuel level sender for a very popular Cessna Aircraft model with a rabid and enthusiastic following.

---- Yes the Cessna Cardinal 177 ----

We had sought out common aviation fuel level sensors to copy into our format and we had a few mixed results, for example owners of Cessna 177's would send in the sensors per our request,  but the part numbers of the units supplied only matched up to another model Cessna Aircraft and did not match any of the Cessna Fuel Level drawings we have on hand.  

Finally, last year we got what we were looking for - Senders from an aircraft that matched the P/N for the aircraft. 

Note:  When you get involved in this small segment of aviation - It becomes very clear why fuel level in aviation has a very low reputation.

A Cardinal Aircraft owner tells a better story: 

Anyway, I saw the mention of CiES on one of the Cardinal Flyers Digests and gave them a call.  I spoke with Scott Philiben, who said that they could build them for me, and it would interface correctly with the JPI.  JPI confirmed this.  This was last FEB 2014 when I initially purchased the JPI, based on that answer.  

I had to wait till July 1 to start install, both due to the cold weather here, and because that was my annual date  (I also wanted to install an Oilamatic Pre-oiler and an Alpha Systems AOA Gauge).  

What Scott didn't tell me initially, was that I was to be the guinea pig for them getting a TSO sender for Cardinals as this minor variation needed to be sent to the FAA and approved - they had predicted an October delivery.

Scott & company finally came thru with fully TSO'd senders in late Nov, but I then encountered the passing of my Mom, which has led to further down time - anyway, FINALLY got the senders installed last Saturday.

CiES Above - Competitor Below

I was quite impressed on the substantial difference internally between CiES senders and the Electronics International ones.  The electronics in CiES look great, and based on the digital freq meter I have, they work VERY smoothly. I am also impressed with the machining on the fuel senders.

For JPI's part, their wire harness to the wing has three wires - +5V, Ground, and Signal. The JPI diagram says NOT to connect the +5V for CiES, but what they didnt say, and I didnt know until early Nov (when I mentioned that to Scott at CiES) is that the CiES units need +12V!! Turned out not to be an issue - the JPI harness has a "Y" connection in the harness shortly after the harness leaves the JPI box enroute to the wings - I unpinned the +5 wire that comes from the JPI and capped it off, and instead ran a +12 supply from one of the Circuit Breakers (dont remember which at the moment) into the same pin spot. (There is NO interface box as there is with some other senders. Not sure if my JPI is any different internally - JPI could answer though.) Works great (again, on my digital freq meter out at the sender)

One thing I particularly like about the CiES is that the float arm wire is 3x as thick as the one from Cessna, BUT the CiES float arm easily disconnects from the sender, making installation MUCH MUCH MUCH easier. I placed a long tie wrap on the fuel sender arm (in case I dropped the float/arm combination into the tank while working the sender into position) and then after the sender was connected and small cotter pin inserted, the tie wrap was removed. The senders come with a new rubber gasket, and there is no chance of leakage in the middle (like Cessna supplied Rochester, Stewart Warner, or Leigh senders) as there is no pass-thru screw terminal.  CiES uses a 3-pin connector with a twist lock shield. VERY easy to plug in.

At first, Scott and his engineers were concerned about MIN/MAX settings, but they had an epiphany one night and realized that all measurements are relative. They were worried about setting hard "stops" these are the little metal tabs on Cessna original equipment fuel senders that limit the float arm travel.   Turns out the CIES senders have the capability to move thru-out an almost 180 degree range from straight down to straight up.  The original equipment Cessna fuel sender contained a 60 degree potentiometer which limited the angle range allowed by these senders.   The calibration in the JPI is what establishes the fuel level limits and the physical limits of the fuel tank are the physical limits of the sender.

Scott Philiben's phone number is 541-408-1095 - they are in Oregon, so there is a 3hr time difference for me. His email is scott.philiben@ciescorp.com I still have the prototype sender/float combination that we used for testing and verification that this new simpler configuration would not hit any internal ribs/structure. Can't see internally, but externally it looks exactly like the ones with the TSO labels on them!

Update - Installed and calibrated - first impressions are good 

TSO'd Turbine Helicopter Fuel Level Sender

Turbine Helicopter                Fuel Level Sender 

It is interesting to us to see where our unique fuel level technology turns up next.   We are making rapid progress making CiES the company to turn to for aviation fuel level.

This is the 3rd new configuration we have revealed this week alone, and there are several we can't talk about at the moment.  Each one is on a more sophisticated platform than the next.

Our technology is simple, reliable and not in contact with the fuel.  It makes for a robust and effective helicopter or turboprop fuel level system.

We had several new challenges to measure a tank of 40" or 100 cm.  We rose to the opportunity and we developed new technology to effectively handle this fuel depth, as well as reporting fuel temperature.

Our combination of simple float and sophisticated sensor technology has proven itself to be the "Go To" technology to provide fuel level in all aviation applications. 

This design is an expansion of our Cirrus SF50 Jet design.

Tecnam Fuel Level Sensor

A few blog post ago we talked about our  UNIVERSAL AIRCRAFT FUEL SENDER and the opportunities that this would open up for us in the aviation market.

Today we will be delivering units for several applications and customers.

Tecnam after first trying to utilize Capacitive Fuel Level Sensors for their aircraft and not being satisfied with their performance decided to try CiES. 

Our success on the Cirrus platforms - Both SR2X Series and the Jet warranted a close look at our technology and capability.

This is the first pair of Tecnam Fuel level sensors.

Magneto Resistive is an excellent technology to apply to fuel level solutions.

It is robust, non-contact, reliable and very accurate.


Let us know about your critical fuel level challenge -
  

A Universal Aircraft Fuel Sender

A UNIVERSAL FUEL SENDER

When we started manufacturing fuel level senders,  we had a specific customer in mind.   

In order to maximize our customers benefit for this technology, we made this sender nearly exclusive for that customers application. 

We received quite few inquiries for this fuel sender and most of them related to will it interface to our existing system.  

Sadly because we had tailored the sender to a particular aircraft and avionics interface,  we had to turn good business away.  

So step forward 3 years nearly to the day,  we had an opportunity to reinvent the fuel sender product and add new features:

First:   We have utilized a unique circuitry design to create a universal output:
                         - We can supply:  Resistance
                                                      Voltage
                                                      Frequency 

Second:  We can supply a  Fuel Temperature Output.  This feature is helpful for Jet A applications  where Pounds Fuel is the unit of measure.

Third:  We have supplied a pigtail to allow installation in tight spaces and flexibility in the Fuel Sender connection. 

We are trying to remove any barrier for you to have a more reliable technology for fuel level in your aircraft.

Contact Us for more information.