Private pilot flying light twin encounters wind shear and turbulence during landing flare at 42B. Ai...

Narrative:

The flight departed shd and was an uneventful flight on an INS flight plan. IFR was cancelled after making visibility contact with the airport about 7 mi away. The approach started with a crosswind entry to runway 14 and normal left pattern throughout. The windsock was observed to be almost fully extended, but lined up quite well with runway 14. Light turbulence was observed in the pattern on approach. The passenger (a licensed and appropriately rated pilot) had observed on final that this was really a 'nice approach.' the final notch of flaps was engaged on final and airspeed was gradually decreased down final to about 80 VMC) over the threshold, which is a normal approach to a short runway (in this case, about 2100'). A normal landing was in progress over the threshold, but with about 10' of altitude remaining some sort of wind shear was encountered and all lift was suddenly lost. The plane dropped and a very hard impact was sustained. Control of the airplane was maintained on rollout and no damage was actually indicated until the engine was stopped and the propeller could be observed. 4 impact marks were observed on the runway surface where the problem struck the runway. While walking around the approach end of the runway immediately after the incident, my personal observation was that the wind was swirling around quite a bit while the windsock indicated a fairly steady wind. In my opinion it is quite possible that a significant wind shear did exist at the time and point of landing and that this is what caused the incident. To the best of my knowledge, there was nothing that could have been done to prevent this incident. The approach was normal in all respects until the very end. The aircraft was in airworthy condition and all systems were functioning. Wind shear is so sudden and unpredictable, I have no recommendations to offer that will prevent a similar event. Supplemental information from acn 136179: suggestion: note addition to airport facility directory concerning possible wind shear on approach to runway at 42B. It is my opinion that the hills, river and proximity to the ocean can contribute to the wind shear potential at 42B.

Original NASA ASRS Text

Title: PVT PLT FLYING LIGHT TWIN ENCOUNTERS WIND SHEAR AND TURBULENCE DURING LNDG FLARE AT 42B. ACFT HITS RWY HARD AND DAMAGES PROPELLER TIPS.

Narrative: THE FLT DEPARTED SHD AND WAS AN UNEVENTFUL FLT ON AN INS FLT PLAN. IFR WAS CANCELLED AFTER MAKING VIS CONTACT WITH THE ARPT ABOUT 7 MI AWAY. THE APCH STARTED WITH A XWIND ENTRY TO RWY 14 AND NORMAL LEFT PATTERN THROUGHOUT. THE WINDSOCK WAS OBSERVED TO BE ALMOST FULLY EXTENDED, BUT LINED UP QUITE WELL WITH RWY 14. LIGHT TURB WAS OBSERVED IN THE PATTERN ON APCH. THE PAX (A LICENSED AND APPROPRIATELY RATED PLT) HAD OBSERVED ON FINAL THAT THIS WAS REALLY A 'NICE APCH.' THE FINAL NOTCH OF FLAPS WAS ENGAGED ON FINAL AND AIRSPD WAS GRADUALLY DECREASED DOWN FINAL TO ABOUT 80 VMC) OVER THE THRESHOLD, WHICH IS A NORMAL APCH TO A SHORT RWY (IN THIS CASE, ABOUT 2100'). A NORMAL LNDG WAS IN PROGRESS OVER THE THRESHOLD, BUT WITH ABOUT 10' OF ALT REMAINING SOME SORT OF WIND SHEAR WAS ENCOUNTERED AND ALL LIFT WAS SUDDENLY LOST. THE PLANE DROPPED AND A VERY HARD IMPACT WAS SUSTAINED. CONTROL OF THE AIRPLANE WAS MAINTAINED ON ROLLOUT AND NO DAMAGE WAS ACTUALLY INDICATED UNTIL THE ENG WAS STOPPED AND THE PROP COULD BE OBSERVED. 4 IMPACT MARKS WERE OBSERVED ON THE RWY SURFACE WHERE THE PROB STRUCK THE RWY. WHILE WALKING AROUND THE APCH END OF THE RWY IMMEDIATELY AFTER THE INCIDENT, MY PERSONAL OBSERVATION WAS THAT THE WIND WAS SWIRLING AROUND QUITE A BIT WHILE THE WINDSOCK INDICATED A FAIRLY STEADY WIND. IN MY OPINION IT IS QUITE POSSIBLE THAT A SIGNIFICANT WIND SHEAR DID EXIST AT THE TIME AND POINT OF LNDG AND THAT THIS IS WHAT CAUSED THE INCIDENT. TO THE BEST OF MY KNOWLEDGE, THERE WAS NOTHING THAT COULD HAVE BEEN DONE TO PREVENT THIS INCIDENT. THE APCH WAS NORMAL IN ALL RESPECTS UNTIL THE VERY END. THE ACFT WAS IN AIRWORTHY CONDITION AND ALL SYSTEMS WERE FUNCTIONING. WIND SHEAR IS SO SUDDEN AND UNPREDICTABLE, I HAVE NO RECOMMENDATIONS TO OFFER THAT WILL PREVENT A SIMILAR EVENT. SUPPLEMENTAL INFO FROM ACN 136179: SUGGESTION: NOTE ADDITION TO ARPT FAC DIRECTORY CONCERNING POSSIBLE WIND SHEAR ON APCH TO RWY AT 42B. IT IS MY OPINION THAT THE HILLS, RIVER AND PROX TO THE OCEAN CAN CONTRIBUTE TO THE WIND SHEAR POTENTIAL AT 42B.

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.

Attributes
ACN	135897
Time
Date	199002
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : 42b
State Reference	CT
Altitude	agl bound lower : 0 agl bound upper : 10
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Small Aircraft, Low Wing, 2 Eng, Retractable Gear
Flight Phase	landing other
Route In Use	approach : straight in
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot oversight : pic
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 24 flight time total : 427 flight time type : 19
ASRS Report	135897
Person 2
Affiliation	Other
Function	observation : passenger
ASRS Report	136179
Events
Anomaly	inflight encounter : weather other anomaly
Independent Detector	other flight crewa
Resolutory Action	none taken : insufficient time
Consequence	other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other
Situations
Publication	Unspecified

Private pilot flying light twin encounters wind shear and turbulence during landing flare at 42B. Aircraft hits runway hard and damages propeller tips.