Reconstructing the Flight

Part 121 operations have one other advantage that a lot of general aviation pilots may not be aware of. All major carriers now have a Flight Operations Quality Assurance (FOQA) program that analyzes the data from the flight data recorders to look for operational trends that might lead to an accident in the future if not corrected. FOQA programs got started in Europe in the mid-1970s when airlines realized there was a wealth of information on flight data recorders that could be utilized to enhance the safety and effectiveness of their flight operations.

The FOQA programs are not used to "spy" on flight crews. Instead, de-identified data from all flights is analyzed by computers to search for trends that could ultimately result in an accident. In one example cited by Christopher Jesse of the Institute of Industrial Research at the University of Portsmouth, England, an airline's FOQA program discovered that its aircraft were often slowing to V2 after takeoff. The flight data showed that pilots were pitching the aircraft too high in the initial climb, resulting in a reduction in airspeed. An engine failure at that point could have resulted in a serious incident or even an accident. The airline could use this information to adjust its training program to address the problem.

The FOQA programs rely on heavy, expensive flight data recorders, putting this type of data analysis beyond the financial means of charter or corporate operators, flight schools or individual pilots. To overcome this problem, UHL Research Associates (uhlflight.com) has spent the last 12 years developing a Flight Reconstruction System (FRS) that weighs less than two pounds and is available for under $4,000.

The UHL-FRS has a one-pound flight recorder that is a refinement of a system developed by David Ellis to eliminate the need for a barograph on competitive glider flights. It utilizes an internal GPS, a solid-state gyroscope and a highly accurate 10 G three-axis accelerometer to take a digital snapshot of what the aircraft is doing every 10th of a second. It also includes a less accurate 50 G three-axis accelerometer that can record the forces experienced during a crash.

The data is stored in a hardened memory unit that can hold up to 8,000 hours of flight data and is typically placed in the tail to enhance survivability in case of an accident. The memory unit is connected by a data cable to the flight recorder, which also has inputs for dynamic and static pressure, gear and flap position, and other aircraft system status information that can be recorded if desired. The flight recorder also has a flash card interface that allows the data from the memory to be extracted for analysis.

The reason the hardware is so simple and inexpensive is that most of the work is done after the data is removed from the aircraft by software developed by Urban Lynch, the founder of UHL Research Associates. The software takes about 20 seconds to analyze a one-hour flight and produce a three-dimensional wire frame reconstruction of that flight with both an external view and an out of the cockpit view. Over 18 other parameters are also available for each data point, including heading, airspeed, altitude, bank angle, and pitch, yaw and roll attitude. The reconstructed flight can be viewed real time, or any specific point of the flight can be analyzed in detail. A blue line shows the path of the aircraft through the air, while a green line shows the path across the ground. Yellow lines are used to indicate desired flight tracks and stabilized approach windows, while white lines show runways.

Lynch has been testing and refining the Flight Reconstruction System over the past decade. For example, the U.S. Air Force is very interested and spent 21 hours testing the system on the F-15, F-16 and T-38. They found that the output was 95 percent accurate when compared with the actual aircraft parameters, and said this was "good enough" for their application. Even better, the software can combine the output from 32 separate aircraft to help analyze air combat maneuvering or aerobatic team performance.

The applications for this system are almost unlimited. While every operator could benefit from the analysis of operating parameters and variances, there are specific benefits for some applications:

Aircraft Manufacturers: Quartz Mountain Aerospace (qmaero.com), formerly Luscombe Aircraft, will be equipping every airplane they sell with the Flight Reconstruction System. They found that both the insurance companies and the leasing company they will be selling to are very interested in the system, as it could protect them by showing whether an accident was caused by an aircraft malfunction or pilot error. Quest Aircraft Company (questaircraft.com) will be putting the FRS into all the Kodiak single-engine turboprops they deliver.

Flight Schools: I am very familiar with the advantage of being able to reconstruct an instructional flight. At SimuFlite we would generate printouts of various maneuvers and approaches to show the pilots exactly how they did. We could also tape the cockpit view during various maneuvers. It is often hard to describe exactly how the pilot was over-controlling on an approach. With the FRS, the student can see exactly what he was doing in real time. As they say, a picture is worth a thousand words, and the pilots often couldn't wait to see the tape after a session to help them understand and learn from the mistakes they had made. I could see how this could even become a marketing factor for schools that equip their aircraft with the FRS, as it would greatly enhance the effectiveness of the debriefing session after an instructional flight, allowing students to progress more rapidly.

The FRS can also help flight schools monitor student solo flights and keep track of how rental pilots are operating their airplanes. One flight school in Malaysia that equipped an airplane with the FRS system was surprised to learn that a student pilot on a solo cross-country flight did not follow the intended flight plan, but instead wandered off to different areas where he was not supposed to go. This kind of blatant disregard for the rules could easily lead to an accident in the future. Aerobatic Teams and Military Flight Operations: Since the UHL software can combine the recordings from up to 32 aircraft into one presentation, it would be very useful for an aerobatic team to analyze their performance. The military can use it for training in aerial combat maneuvering, allowing each pilot to see exactly how they flew and the effectiveness of various maneuvers.

Post-Accident Analysis: This is where the FRS would really pay for itself. One of the most frustrating issues in general aviation is that many times we have no idea why an airplane crashed. This often leads to complicated litigation with the pilot's estate blaming the manufacturer and the manufacturer blaming the pilot. An FRS would show investigators exactly what happened, which could reduce expensive litigation and hopefully result in reduced insurance rates for everyone.

Mission Aviation Fellowship (MAF) has already experienced the power of this system. They tested eight demonstration recorders in some of the most difficult flying in the world to verify the accuracy of the units. During the demonstration period, an FRS-equipped airplane landed short of the runway in Indonesia at a remote landing strip that requires strict adherence to the specified approach procedure.

Ordinarily it would have been assumed that the pilot had somehow lost his focus and caused the accident. By analyzing the FRS recording for this and other landings at this location, MAF determined that the pilot had done everything right, and that there were dangerous wind gusts at certain times of the day that necessitated going to more conservative wind restrictions at that strip. Dave Rask, the manager of Aviation Safety for MAF, said they are going to install the FRS in additional aircraft and eventually hope to equip their entire fleet worldwide with this system.

Summary With any new system that monitors aircraft operation, there is bound to be resistance from pilots and instructors who don't like the idea of anyone looking over their shoulders at everything they do. Once pilots understand that the data is typically used for de-identified trend and variance analysis to improve flight operations, and that it can exonerate a pilot after an incident or accident that was not their fault, I believe the inherent value in this system will become evident. Over time, the information derived from many flights and accidents could allow us all to learn how to avoid those kinds of accidents in the future, ultimately saving lives by reducing the number of people who die each year in general aviation accidents.