Narrative:

Descent into lch was normal, with WX at 1800' overcast, visibility 2 mi, wind 070 degrees at 20 KTS, gusting to 28 KTS. The aircraft was descended under control of lck approach control following light transport Y for an ILS approach to runway 15 on a left downwind entry. Approach cleared light transport X to tower and cleared to land. Light transport X was extended past the OM for a left turn onto the localizer. Approaching the OM, I asked the controllers for the runway conditions and if any problems landing with preceding light transport Y. The reply was: 'braking good,' with a 10 KT airspeed deviation. Preceding light transport Y had landed and light transport X was cleared to land. The ILS was normal down to T/D. During the phase of rollout, approximately 2000' down the runway, gust loads increased rapidly. The aircraft touched down approximately 500' from the end of the runway. Gust loads were increasing rapidly at about 4000' down the runway and the aircraft was down to about 40-45 KTS and estimated final distance of 5200' when the aircraft was suddenly gripped with winds of 70-75 mph downburst. Aircraft was blown off the right side of the runway into the grass medium. Aircraft stopped in about 60' of roll. No injuries to any member on board. Aircraft blew right main outboard tire when exiting runway upon passing over runway light. It was revealed later to the crew that airport wind anemometer is located 1/4-1/2 mi north of the airport control tower and is not on the airport itself. Even though the WX was gusty with moderate rain, it did not appear out of limits and with the previous light transport Y landing 4 mins ahead, it was deemed appropriate to continue the landing. It was totally unexpected when during rollout the aircraft was hit with an extreme downburst. Wind anemometer is not located on the airport. Readings are taken 1/2 mi off the airport north of the control tower. It is believed no damage to the aircraft would have occurred if the runway edge lights were not mounted on concrete piers 9' above grass grass/ground level.

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Original NASA ASRS Text

Title: LTT ENCOUNTERED STRONG DOWNBURST AND WIND SHEAR ON ROLLOUT AFTER LNDG. ACFT WENT OFF RWY AND BLEW TIRE.

Narrative: DSNT INTO LCH WAS NORMAL, WITH WX AT 1800' OVCST, VISIBILITY 2 MI, WIND 070 DEGS AT 20 KTS, GUSTING TO 28 KTS. THE ACFT WAS DSNDED UNDER CTL OF LCK APCH CTL FOLLOWING LTT Y FOR AN ILS APCH TO RWY 15 ON A LEFT DOWNWIND ENTRY. APCH CLRED LTT X TO TWR AND CLRED TO LAND. LTT X WAS EXTENDED PAST THE OM FOR A LEFT TURN ONTO THE LOC. APCHING THE OM, I ASKED THE CTLRS FOR THE RWY CONDITIONS AND IF ANY PROBS LNDG WITH PRECEDING LTT Y. THE REPLY WAS: 'BRAKING GOOD,' WITH A 10 KT AIRSPD DEVIATION. PRECEDING LTT Y HAD LANDED AND LTT X WAS CLRED TO LAND. THE ILS WAS NORMAL DOWN TO T/D. DURING THE PHASE OF ROLLOUT, APPROX 2000' DOWN THE RWY, GUST LOADS INCREASED RAPIDLY. THE ACFT TOUCHED DOWN APPROX 500' FROM THE END OF THE RWY. GUST LOADS WERE INCREASING RAPIDLY AT ABOUT 4000' DOWN THE RWY AND THE ACFT WAS DOWN TO ABOUT 40-45 KTS AND ESTIMATED FINAL DISTANCE OF 5200' WHEN THE ACFT WAS SUDDENLY GRIPPED WITH WINDS OF 70-75 MPH DOWNBURST. ACFT WAS BLOWN OFF THE RIGHT SIDE OF THE RWY INTO THE GRASS MEDIUM. ACFT STOPPED IN ABOUT 60' OF ROLL. NO INJURIES TO ANY MEMBER ON BOARD. ACFT BLEW RIGHT MAIN OUTBOARD TIRE WHEN EXITING RWY UPON PASSING OVER RWY LIGHT. IT WAS REVEALED LATER TO THE CREW THAT ARPT WIND ANEMOMETER IS LOCATED 1/4-1/2 MI N OF THE ARPT CTL TWR AND IS NOT ON THE ARPT ITSELF. EVEN THOUGH THE WX WAS GUSTY WITH MODERATE RAIN, IT DID NOT APPEAR OUT OF LIMITS AND WITH THE PREVIOUS LTT Y LNDG 4 MINS AHEAD, IT WAS DEEMED APPROPRIATE TO CONTINUE THE LNDG. IT WAS TOTALLY UNEXPECTED WHEN DURING ROLLOUT THE ACFT WAS HIT WITH AN EXTREME DOWNBURST. WIND ANEMOMETER IS NOT LOCATED ON THE ARPT. READINGS ARE TAKEN 1/2 MI OFF THE ARPT N OF THE CTL TWR. IT IS BELIEVED NO DAMAGE TO THE ACFT WOULD HAVE OCCURRED IF THE RWY EDGE LIGHTS WERE NOT MOUNTED ON CONCRETE PIERS 9' ABOVE GRASS GRASS/GND LEVEL.

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.