Reference

CiES Fuel Senders

• Do CiES digital fuel senders have TSO Approval? Does CiES have PMA?

  Yes, the TSO ensures a quality and repeatable fuel level output under all aircraft conditions and STC demonstrates that these senders are suitable for use in specific type certificated aircraft. This is the only TSO'd fuel sender available for retrofit in GA aircraft. TSO approval ensures that the product manufacturing has been accomplished in FAA approved quality system, as such, TSO products do not require PMA.

• Fuel gauges don’t work in the GA aircraft, why would installing your product be different?

  Original resistive aircraft fuel senders were designed to measure approx. 20 gallons and provide a resolution of 0.3 of a gallon between readings. These resistive senders were intended for automotive and farm machinery applications and are typically made of steel. The aircraft application places additional stresses on these commercial products, from moisture born corrosion to large movements in fuel in and out of plane of the sender. CiES designed an aviation-grade fuel sender from the outset. We addressed the moisture borne corrosion issues and also addressed fuel motion in all axis and we designed a system to give excellent resolution. Our resolution capability is less than (1/10 of a gallon) for fuel tanks that can hold hundreds of gallons of fuel.

• How does the CiES sender work?

  The system is easy to understand. We place an aligned magnetic field on the pivot so that this field can be measured by an electronic compass which now points to the float. We place this highly accurate compass inside an aluminum housing and outside the fuel tank measuring the direction of the magnetic field through the aluminum. This solid-state compass electronically points to the float in the same manner that a cell phone compass points to north. It is astoundingly accurate and fuel motion has no impact on operation.

• How reliable is the CiES fuel senders?

  CiES fuel senders have amassed over 800,000 hrs of operation on Cirrus Aircraft with only thirteen removals out of 23,000 senders for cause. This represents a Mean Time to Failure of over 60,000 hrs. This reliability exceeds every other system on the Cirrus aircraft. Cirrus is so impressed that they specified CiES technology on the Cirrus Jet. To back that amazing reliability, we warranty the senders for non-transferable life.

• I have a fuel totalizer, why would I need a working fuel gauge?

  A functional fuel gauge is required by regulation and is supposed to work as the manufacturer intended. While some people in aviation cast a broad net on what working means, according to the FAA, it means the ability to accurately show usable fuel in each tank. Gauges that waver or show merely a trend in operation are not functional. Fuel gauges are required, as it takes the fundamental issue of pilot first impression of starting fuel level out of the equation as well as any other fuel anomalies that could happen in flight.

• I heard fuel gauges only have to be accurate at zero?

  While even some in the FAA Flight Standards Offices quote this as verbatim truth, it is absolutely not true. CiES works with all of the FAA ACO offices and the FAA Small Aircraft directorate. Usable fuel is an accurate value for every certificated aircraft flying. So yes, zero usable fuel is an accurate number, but so is full usable fuel (that value is on the fuel filler placard and in your POH). Using simple math 1/2 usable fuel is also an accurate number. The zero-fuel accurate myth is just that, a myth.

• We can output an ANALOG SIGNAL to:

  • Aerospace Logic
  • Auracle
  • Avidyne
  • Dynon
  • Garmin
  • Rochester

• What cockpit interfaces do the CiES digital fuel sender interface to?

  We can output a DIGITAL SIGNAL to:

  • Garmin G950, G1000,
  • G500/G600 TXi, G3X, GI275
  • Aerospace Logic FL20XD Series
  • JPI 900, 930, 960
  • EI CGR-30 & MVP-50

• What is the benefit to having accurate fuel level?

  While there are a lot of theories of why pilots run out of fuel, much of what is commonly reported does not have actual research to support the statements. What we know, is that due to our involvement in this business and having Cirrus outfitting the system on new SR20 and SR22 aircraft since 2012 we now have a growing number of aircraft where fuel indication is proven to be reliable and accurate. The rate of fuel accidents or incidents primarily attributed to starving the engine of fuel is zero.* While older Cirrus aircraft, all of which have totalizers, suffer and continue to suffer fuel accidents, this fleet of new aircraft has not suffered a single fuel incident.*

  * We have one incident where a severe heroin addiction was implicated, and an accident where the ferry tank fuel valve failed.

• What is the pedigree of the CiES fuel sender?

  CiES used Cirrus Aircraft, CiES launch partner, to successfully demonstrate that CiES aviation-proven manufacturing and development process yielded a superior product that is suitable for use in all type certificated aircraft. CiES is qualified to RTCA DO-254 and the digital fuel senders exposed to the aircraft environmental conditions for wing mounting by RTCA DO-160.

• Will these sensors work with my existing fuel gauges?

  While CiES designed the sender to be able to output to a resistance input analog fuel gauge, there are several issues that make this interface less than ideal. First - an analog gauge has its own characteristic and that has to be matched to the tank characteristic. This would be, at present, a remove, reprogram and replace proposition until the gauge and tank content correlate. Second - Analog gauging for fuel applied to aircraft utilized gauge interfaces that were not designed to be accurate. We see gauge hysteresis and variations that make accurate fuel reporting nearly impossible. CiES is committed to accurate fuel gauging in aircraft, and these interfaces do not allow that to easily occur. Note: if the original aircraft gauge is the only interface that will work for your aircraft, CiES is working on two potential solutions. One will require rebuilt or qualified aircraft gauging, the other replaces the existing pointer driver with a stepper motor.