|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0601 To 1200|
|Locale Reference||atc facility : sea|
airport : lkisabelle
|Altitude||agl bound lower : 0|
agl bound upper : 0
|Controlling Facilities||tower : fsd|
|Operator||general aviation : instructional|
|Make Model Name||Small Aircraft|
|Flight Phase||landing other|
|Function||flight crew : single pilot|
|Qualification||pilot : instrument|
pilot : commercial
pilot : cfi
|Experience||flight time last 90 days : 150|
flight time total : 1400
flight time type : 900
|Anomaly||inflight encounter other|
other spatial deviation
|Independent Detector||other flight crewa|
|Resolutory Action||flight crew : declared emergency|
none taken : unable
none taken : detected after the fact
|Primary Problem||Flight Crew Human Performance|
|Air Traffic Incident||Pilot Deviation|
Aircraft was an small aircraft floatplane and the incident involved making a low approach to and inadvertent landing in a high mountain lake, lake isabelle, elevation 2800' MSL, OAT was 40 degrees F. The approach was normal and I have landed many times in this lake in the summer. The lake is adequate in size and has a non-mountainous opening for a safe go around if needed. However, my judgement was inadequate in that I thought that the seemingly ice appearance of the lake surface was actually ice with about 12' of snow cover. I was making a glassy water type of approach (very gentle letdown) and was not concerned with contact of what I thought was ice as there was plenty of room, 4000+' of lake ahead of me. However, as soon as my floats did touch the surface (this was not planned and does happen with glassy water apches and snow/whiteouts), the wet snow created quite a lot of drag and a full landing was the result. There was no damage to the aircraft or personnel, however takeoff was not possible and I had to call and arrange for a helicopter to be taken out. My thoughts on the matter looking back were that I was dealing with a situation beyond my experience level and that it was a learning experience.
Original NASA ASRS Text
Title: GA SMA LNDG ON A FROZEN LAKE COVERED WITH 12 INCHES OF SNOW AND WAS UNABLE TO TKOF. ACFT STRANDED AND HELICOPTER CALLED TO TRANSPORT PLT.
Narrative: ACFT WAS AN SMA FLOATPLANE AND THE INCIDENT INVOLVED MAKING A LOW APCH TO AND INADVERTENT LNDG IN A HIGH MOUNTAIN LAKE, LAKE ISABELLE, ELEVATION 2800' MSL, OAT WAS 40 DEGS F. THE APCH WAS NORMAL AND I HAVE LANDED MANY TIMES IN THIS LAKE IN THE SUMMER. THE LAKE IS ADEQUATE IN SIZE AND HAS A NON-MOUNTAINOUS OPENING FOR A SAFE GO AROUND IF NEEDED. HOWEVER, MY JUDGEMENT WAS INADEQUATE IN THAT I THOUGHT THAT THE SEEMINGLY ICE APPEARANCE OF THE LAKE SURFACE WAS ACTUALLY ICE WITH ABOUT 12' OF SNOW COVER. I WAS MAKING A GLASSY WATER TYPE OF APCH (VERY GENTLE LETDOWN) AND WAS NOT CONCERNED WITH CONTACT OF WHAT I THOUGHT WAS ICE AS THERE WAS PLENTY OF ROOM, 4000+' OF LAKE AHEAD OF ME. HOWEVER, AS SOON AS MY FLOATS DID TOUCH THE SURFACE (THIS WAS NOT PLANNED AND DOES HAPPEN WITH GLASSY WATER APCHES AND SNOW/WHITEOUTS), THE WET SNOW CREATED QUITE A LOT OF DRAG AND A FULL LNDG WAS THE RESULT. THERE WAS NO DAMAGE TO THE ACFT OR PERSONNEL, HOWEVER TKOF WAS NOT POSSIBLE AND I HAD TO CALL AND ARRANGE FOR A HELI TO BE TAKEN OUT. MY THOUGHTS ON THE MATTER LOOKING BACK WERE THAT I WAS DEALING WITH A SITUATION BEYOND MY EXPERIENCE LEVEL AND THAT IT WAS A LEARNING EXPERIENCE.
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.