Deccan Charters’ VT-DCE, which has a G1000 flight deck. The G1000 supports data logging, sufficient for FDM and FOQA needs.
The Flying Engineer explores regulations covering flight recorders, and how even in the absence of the mandate for such devices in single engine and piston aircraft, a commonly found avionics suite allows the operator to tackle flight safety: proactively.
The Indian Director General of Civil Aviation (DGCA), in its civil aviation regulations (CAR) Section 2 Series “I” Part V Issue II, dated 23rd January 2013, covers flight data recorders (FDR), and describes a FDR as “Any type of recorder installed in the aircraft for the purpose of complementing accident/incident investigation.”
The same regulation does not talk about FDR for single engine airplanes. The closest it comes to is a recommendation, for commercial transport, and general aviation, “that all turbine-engined aeroplanes of a maximum certificated take-off mass of 5700kg or less for which the individual certificate of airworthiness is first issued on or after 1 January 2016 should be equipped with: a) a Type II FDR; or b) a class C AIR capable of recording flight path and speed parameters displayed to the pilot(s);or c) an ADRS capable of recording the essential parameters”
A recommendation is not enforceable, and single engine pistons are not covered.
Interestingly, CAR Section 3 (Air Transport) Series C Part III Issue II, dated 1st June 2010, talks of the minimum requirement for the grant of a Non-Scheduled Operator Permit (NSOP). The CAR covers single engine turbine, and single engine piston aircraft as well. The regulation also describes the need to demonstrate a “Flight Operations Quality Assurance (FOQA) and CVR/FDR monitoring system.”
Flight Data Monitoring (FDM) is defined as “the pro-active use of recorded flight data from routine operations to improve aviation safety.” FDM is important, as a review of recorded flight can identify deviations and exceedances, which can be used for corrective training. It is an effective method where an incident is analyzed, and brought to the notice of flight & maintenance crew before it amplifies to an accident.
The surprise here is the DGCA’s realization of the importance of FDM & FOQA in aviation, irrespective of the airplane type, but it’s very regulations do not cover FDRs in single engine airplanes.
Infact, piston engine, whether multi or single engine, are not covered: “All multi-engined turbine powered aeroplanes of a maximum certificated takeoff mass of 5700kg or less for which the individual certificate of airworthiness is first issued on or after 1 January 1989, shall be equipped with a Type II FDR by 31.12.2013.”
Either DGCA assumes that pistons have no future, or that operators, both commercial and general aviation, fly only turbines.
The benefits of FDM
FDM is beneficial for everybody, right from the student pilot to the airline pilot. In training, FDM is necessary to immediately identify exceedances and deviations, bringing it to the notice of the concerned. For example, a student pilot who pulled a high G maneuver may have stressed an airframe, and if before scheduled inspections, the airframe is stressed multiple times, a failure could result. Similarly, a private pilot with 50-60 hrs may make mistakes, which may go unnoticed unless an expert, or a sufficiently experienced person goes through the flight data recordings to understand and point out what went wrong, and how it may be avoided. These are small steps toward enhanced safety for all.
Flight Data Recording without a FDR
G1000 for a Cessna 172
Garmin’s G1000 has been adopted by many airframe manufacturers, making it a standard fit on their aircraft. Cessna for one, offers the G1000 from the 172R to its turbine single engines, including the Grand Caravan.
The Garmin G1000 features flight data logging (FDL), which is not a FDR, but may be used for the same purpose: FDM & FOQA.
On the 172, the G1000 for Cessna: NAV III, logs 64 parameters, at a 1 second interval. These parameters cover (and exceed) the requirements laid down in the regulations for an Aircraft Data Recording System (ADRS), but fall short on only 2 aspects: the recording interval (some data needs to be recorded at 250ms intervals, but is logged in the G1000 in 1 second intervals), and the control surface position (primary and secondary flight control positions are not recorded).
States the Garmin Manual, “The Flight Data Logging feature will automatically store critical flight and engine data on an SD data card inserted into the top card slot of the MFD. Approximately 4,000 flight hours can be recorded on the card.”
In addition, Garmin provides a free, simple to use software that in a few clicks converts the recorded flle to a Google Earth path, which can be viewed in 3D to visually analyze the flight path.
A side-by-side shot of the regions of the MFD where the SD card for flight logging is inserted. One aircraft has it inserted, while the other has it missing, losing the benefits of FDM.
The Flying Engineer has flight data logs from a Cessna 172R for two flights spanning over 2 hours, and the parameters have been so exhaustive that it has supported academic use of the data.
VT-FGE, the ill-fated Diamond DA40CS that crashed in the December of 2013 when on a training flight, has the logging functionality. With the log, it will be immediately clear as to what went wrong, playback of which will prevent other students from repeating the same mistakes.
Unfortunately, schools and some private operators record the data, but do not have a program to pro-actively monitor and analyze every flight, every day, missing an opportunity to self learn and proactively enhance flight safety.
With the Indian GAGAN (GPS-aided geo-augmented navigation) system expected to be fully operational by year end, The Flying Engineer visited a Diamond DA40NG today, at Bangalore, to check if the aircraft was SBAS (Satellite Based Augmentation System) enabled, and how GPS information is presented.
GPS is the acronym for the Navstar Global Positioning System, a space-based radio navigation system owned by the United States Government (USG) and operated by the United States Air Force (USAF). Due to its global availability, the Navstar GPS is a Global Navigation Satellite System (GNSS).
A SBAS system, in principle, detects errors responsible for low accuracy and integrity of GPS receiver positions, and broadcasts those errors via geostationary satellites. SBAS enabled GPS receivers apply these corrections, to compute a more accurate GPS position, with 99.99999% certainty. Sources of errors include the satellite (timing errors), and signal propagation delay (as it passes through the ionosphere). Satellite errors are applicable worldwide, but ionosphere errors are location specific.
The Garmin G1000 system relies on the GIA 63 IAU (Integrated Avionics Unit), which functions as the main communications hub, linking all other units (LRUs) with the PFD. Each IAU contains a GPS receiver, a very high frequency (VHF) communication/navigation/glideslope (COM/NAV/GS) receiver, and system integration microprocessors. The GIA 63W (Note the extra “W”) contains a GPS WAAS receiver. WAAS is the United States’ SBAS.
Although labeled as a WAAS receiver, the unit can receive satellite corrections from other operational SBAS as well: Europe’s EGNOS, and Japan’s MSAS, as seen in the photo on the left.
When GAGAN becomes fully operational, supporting ILS CAT-I like GPS approaches, Garmin International is expected release a navigation database update cycle that will allow the Garmin G1000 display units to list the GAGAN system under “SBAS Selection”. It may then be prudent to de-select WAAS, EGNOS and MSAS, and select only GAGAN.
The GPS Signal Strength box, as seen in the GPS Status page, in the photo on the right, shows the GPS satellites (these satellites have a code, called a PRN (Pseudo Random Noise), between 1 and 32), and the SBAS satellites (124, 126, 129). Satellite 124 is Artemis (EGNOS), 126 is INMAR3F5 (EGNOS), and 129 is MTSAT1R (MSAS).
GAGAN’s SBAS satellites, GSAT-8 and GSAT-10, will be seen as satellites with PRN 127 and 128, respectiely.
The green bars show satellites that are actually being used in the position calculation, the height of the bar proportional to the signal strength. The blue bar shows satellite 25 is locked on but not yet being used in the position calculation. The hollow signal strength bars for satellites 31, 126 and 129 show that the receiver has found the satellite and is collecting data, before the satellite may be used for navigation, and the bar becomes solid. No signal strength bar, as seen for satellite124, shows that the receiver is looking for the indicated satellite.
The “D" indication on signal strength bar shows that the satellite is being used for differential computations. The differential computations, which is the consideration of the “error” to improve positional accuracy, is based on transmissions from EGNOS and MSAS. Since India is not in the intended geographical coverage area of EGNOS or MSAS (see image above, courtesy AAI), Ionosphere corrections are unavailable, but satellite error corrections, which are globally valid, are available, and being used.
With these corrections, the Estimated Position Uncertainty (EPU): the radius of a circle centered on the GPS estimated horizontal position in which actual position has 95% probability of lying, is 0.05NM, as seen in the Satellite Status Box.
The Horizontal and Vertical Figures of Merit (HFOM and VFOM), seen as 23ft and 33ft respectively, is the current 95% confidence horizontal and vertical accuracy values reported by the GPS receiver.
Based on GAGAN’s trials by the Airport Authority of India (AAI), the observed accuracies are 3ft horizontal and 5ft vertical: a dramatic increase in positional accuracy, which the same aircraft will observe when the GAGAN is switched on for civilian use: something that is hoped to happen by the end of Jan 2014, as per the AAI General Manager (CNS) heading the Ground Based Elements of the GAGAN Project at Bangalore, India.
A 5 month sabbatical from my website (I continued to write for my print magazine, Airbuz) was well spent. I engaged myself in the design and development of a General Aviation Flight Simulator. Either click HERE to know more, or visit my section, “Projects”.
I must thank my readers who were both patient and concerned. I hope you like the simulator!