 |
37000 Feet | Browse and search NASA's Aviation Safety Reporting System |
|
An L2K experimental pilot reported a gradual loss of aircraft control during a maneuver to dissipate static electricity near farmington, NM.
| Attributes | |
| ACN | 570925 |
| Time | |
| Date | 200301 |
| Day | Sat |
| Local Time Of Day | 1201 To 1800 |
| Place | |
| Locale Reference | airport : fam.airport |
| State Reference | NM |
| Altitude | msl bound lower : 20500 msl bound upper : 21000 |
| Environment | |
| Flight Conditions | VMC |
| Light | Daylight |
| Aircraft 1 | |
| Controlling Facilities | artcc : zab.artcc |
| Operator | general aviation : personal |
| Make Model Name | Experimental |
| Operating Under FAR Part | Part 91 |
| Flight Phase | cruise : level |
| Route In Use | arrival : on vectors |
| Flight Plan | IFR |
| Person 1 | |
| Affiliation | other |
| Function | flight crew : single pilot |
| Qualification | pilot : instrument pilot : commercial pilot : multi engine pilot : cfi pilot : atp |
| Experience | flight time last 90 days : 50 flight time total : 2700 flight time type : 150 |
| ASRS Report | 570925 |
| Person 2 | |
| Affiliation | government : faa |
| Function | controller : radar |
| Events | |
| Anomaly | aircraft equipment problem : critical altitude deviation : excursion from assigned altitude non adherence : clearance non adherence : far non adherence : published procedure other anomaly |
| Independent Detector | other flight crewa |
| Resolutory Action | flight crew : exited adverse environment flight crew : regained aircraft control |
| Consequence | faa : reviewed incident with flight crew other |
| Supplementary | |
| Problem Areas | Flight Crew Human Performance Environmental Factor Aircraft |
| Primary Problem | Flight Crew Human Performance |
| Air Traffic Incident | Pilot Deviation |
Narrative:
I was flying my experimental at FL210, when I noticed a gradual loss of radio communications. I could still hear ATC and other aircraft with the squelch turned off, but they could not hear me. I have had this problem intermittently in the flight levels, and I have been reading about static electricity issues in aircraft. One of the suggestions that I have read is that a change in airspeed can dissipate the static field. With the autoplt engaged, I reduced throttle. Unfortunately, I failed to take into consideration that the autoplt is programmed to automatically recover if it senses the airspeed drop below a preprogrammed minimum. At about 100 KTS, the autoplt abruptly dove to recover airspeed, and it took me 500 ft to recover back to FL210. Lesson: I could hear ATC, and could at a minimum respond to their communications with an identify. Flirting with stalls in thin air is unwise in this aircraft, as it has viscous stall characteristics, even at lower altitudes. I was able to reach ATC when I flew directly over their receiver, and I requested 17000 ft. At that altitude, the radio problems disappeared. Even when I was higher, I could reach ATC by talking to other aircraft who could hear me. There was simply no need to take the risk.
Original NASA ASRS Text
Title: AN L2K EXPERIMENTAL PLT RPTED A GRADUAL LOSS OF ACFT CTL DURING A MANEUVER TO DISSIPATE STATIC ELECTRICITY NEAR FARMINGTON, NM.
Narrative: I WAS FLYING MY EXPERIMENTAL AT FL210, WHEN I NOTICED A GRADUAL LOSS OF RADIO COMS. I COULD STILL HEAR ATC AND OTHER ACFT WITH THE SQUELCH TURNED OFF, BUT THEY COULD NOT HEAR ME. I HAVE HAD THIS PROB INTERMITTENTLY IN THE FLT LEVELS, AND I HAVE BEEN READING ABOUT STATIC ELECTRICITY ISSUES IN ACFT. ONE OF THE SUGGESTIONS THAT I HAVE READ IS THAT A CHANGE IN AIRSPD CAN DISSIPATE THE STATIC FIELD. WITH THE AUTOPLT ENGAGED, I REDUCED THROTTLE. UNFORTUNATELY, I FAILED TO TAKE INTO CONSIDERATION THAT THE AUTOPLT IS PROGRAMMED TO AUTOMATICALLY RECOVER IF IT SENSES THE AIRSPD DROP BELOW A PREPROGRAMMED MINIMUM. AT ABOUT 100 KTS, THE AUTOPLT ABRUPTLY DOVE TO RECOVER AIRSPD, AND IT TOOK ME 500 FT TO RECOVER BACK TO FL210. LESSON: I COULD HEAR ATC, AND COULD AT A MINIMUM RESPOND TO THEIR COMS WITH AN IDENT. FLIRTING WITH STALLS IN THIN AIR IS UNWISE IN THIS ACFT, AS IT HAS VISCOUS STALL CHARACTERISTICS, EVEN AT LOWER ALTS. I WAS ABLE TO REACH ATC WHEN I FLEW DIRECTLY OVER THEIR RECEIVER, AND I REQUESTED 17000 FT. AT THAT ALT, THE RADIO PROBS DISAPPEARED. EVEN WHEN I WAS HIGHER, I COULD REACH ATC BY TALKING TO OTHER ACFT WHO COULD HEAR ME. THERE WAS SIMPLY NO NEED TO TAKE THE RISK.
Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.