|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||atc facility : emt|
|Altitude||msl bound lower : 4500|
msl bound upper : 11000
|Controlling Facilities||tracon : bur|
tower : ewr
|Operator||common carrier : air taxi|
|Make Model Name||Small Aircraft, Low Wing, 1 Eng, Retractable Gear|
|Flight Phase||cruise other|
|Route In Use||enroute : on vectors|
|Affiliation||company : air taxi|
|Function||flight crew : single pilot|
|Qualification||pilot : instrument|
pilot : cfi
pilot : commercial
|Experience||flight time last 90 days : 200|
flight time total : 2300
flight time type : 50
|Affiliation||government : faa|
|Function||controller : approach|
|Qualification||controller : radar|
|Anomaly||aircraft equipment problem : critical|
|Independent Detector||other flight crewa|
|Resolutory Action||controller : issued new clearance|
flight crew : overcame equipment problem
flight crew : declared emergency
I was flying IFR from bakersfield to el monte when my airspeed indicator failed probably due to icing. Preflight had shown a hot pitot static system and I was flying with the pitot heat on. There was only about an eighth inch of ice on the wings and I was descending down towards VFR conditions. A couple of minutes later I was in moderate turbulence making it hard to read the altitude indicator. ATC asked if I was declaring an emergency. I did and received special handling for a couple of minutes until I was VFR underneath (about 4500). I continued on to el monte VFR. Callback conversation with reporter revealed the following: reporter states after pushing mechanics to check further, learned pitot heat can be partially functioning and give the impression of heat on preflight check. In such a situation heat is not great enough to prevent in severe icing conditions. Reporter knows now to let pitot really heat up during preflight to assure full function. No FAA followup.
Original NASA ASRS Text
Title: PITOT ICING, NO AIRSPEED INDICATOR.
Narrative: I WAS FLYING IFR FROM BAKERSFIELD TO EL MONTE WHEN MY AIRSPEED INDICATOR FAILED PROBABLY DUE TO ICING. PREFLT HAD SHOWN A HOT PITOT STATIC SYSTEM AND I WAS FLYING WITH THE PITOT HEAT ON. THERE WAS ONLY ABOUT AN EIGHTH INCH OF ICE ON THE WINGS AND I WAS DSNDING DOWN TOWARDS VFR CONDITIONS. A COUPLE OF MINUTES LATER I WAS IN MODERATE TURB MAKING IT HARD TO READ THE ALT INDICATOR. ATC ASKED IF I WAS DECLARING AN EMER. I DID AND RECEIVED SPECIAL HANDLING FOR A COUPLE OF MINUTES UNTIL I WAS VFR UNDERNEATH (ABOUT 4500). I CONTINUED ON TO EL MONTE VFR. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: REPORTER STATES AFTER PUSHING MECHANICS TO CHECK FURTHER, LEARNED PITOT HEAT CAN BE PARTIALLY FUNCTIONING AND GIVE THE IMPRESSION OF HEAT ON PREFLT CHECK. IN SUCH A SITUATION HEAT IS NOT GREAT ENOUGH TO PREVENT IN SEVERE ICING CONDITIONS. REPORTER KNOWS NOW TO LET PITOT REALLY HEAT UP DURING PREFLT TO ASSURE FULL FUNCTION. NO FAA FOLLOWUP.
Data retrieved from NASA's ASRS site as of August 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.