Narrative:

We were cleared for a visual approach to runway 26L just outside the outer marker, at which time the tower advised us that an aircraft (type unknown) experienced an airspeed fluctuation of about 30 KTS with turbulence. Immediately following the tower advised us that the winds were still calm and no windshear advisories via the windshear equipment were issued. Only that doppler radar testing was in effect. Upon proceeding down the glide path at approximately 400-500' AGL at +/-10 KTS airspeed variation with turbulence occurred, corrective action was taken and a stabilized approach was reestablished. Shortly thereafter all three crew members discussed the possibility of a go-around, but with the situation underhand and flight stabilized with only continuous turbulence at the moment, we elected to continue the approach. At approximately 200' AGL, a quick +/-10-12 KT airspeed fluctuation was again experienced. Again, upon taking corrective action a stabilized approach was reestablished, this time remaining approximately 1/2 DOT above glide slope as a further precaution. From 50' AGL to 'round-out' all turbulence had ceased and we were in smooth, calm conditions with stabilized landing speed. At approximately 1000' down the runway, we experienced floating in ground effect, with still no turbulence, as the floating became excessive, attempting to touch down, at about 5' above the runway, we encountered an excessive downdraft which resulted in a hard landing. In our opinion, a go-around in this position was not an option, since close proximity to the runway and low airspeed would have complicated the situation. Also, an encounter with the mentioned downdraft at a higher altitude than mentioned (5') with a go-around attempt would most likely have resulted in a much harder contact with the runway than experienced. Our company was advised of the mishap, and no injuries occurred.

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Original NASA ASRS Text

Title: ACR LGT HARD LNDG AT DEN, AIRSPEED FLUCTUATIONS HAD BEEN REPORTED BY PRECEDING ACFT.

Narrative: WE WERE CLRED FOR A VISUAL APCH TO RWY 26L JUST OUTSIDE THE OUTER MARKER, AT WHICH TIME THE TWR ADVISED US THAT AN ACFT (TYPE UNKNOWN) EXPERIENCED AN AIRSPEED FLUCTUATION OF ABOUT 30 KTS WITH TURBULENCE. IMMEDIATELY FOLLOWING THE TWR ADVISED US THAT THE WINDS WERE STILL CALM AND NO WINDSHEAR ADVISORIES VIA THE WINDSHEAR EQUIPMENT WERE ISSUED. ONLY THAT DOPPLER RADAR TESTING WAS IN EFFECT. UPON PROCEEDING DOWN THE GLIDE PATH AT APPROX 400-500' AGL AT +/-10 KTS AIRSPEED VARIATION WITH TURBULENCE OCCURRED, CORRECTIVE ACTION WAS TAKEN AND A STABILIZED APCH WAS REESTABLISHED. SHORTLY THEREAFTER ALL THREE CREW MEMBERS DISCUSSED THE POSSIBILITY OF A GO-AROUND, BUT WITH THE SITUATION UNDERHAND AND FLT STABILIZED WITH ONLY CONTINUOUS TURBULENCE AT THE MOMENT, WE ELECTED TO CONTINUE THE APCH. AT APPROX 200' AGL, A QUICK +/-10-12 KT AIRSPEED FLUCTUATION WAS AGAIN EXPERIENCED. AGAIN, UPON TAKING CORRECTIVE ACTION A STABILIZED APCH WAS REESTABLISHED, THIS TIME REMAINING APPROX 1/2 DOT ABOVE GLIDE SLOPE AS A FURTHER PRECAUTION. FROM 50' AGL TO 'ROUND-OUT' ALL TURBULENCE HAD CEASED AND WE WERE IN SMOOTH, CALM CONDITIONS WITH STABILIZED LNDG SPEED. AT APPROX 1000' DOWN THE RWY, WE EXPERIENCED FLOATING IN GND EFFECT, WITH STILL NO TURBULENCE, AS THE FLOATING BECAME EXCESSIVE, ATTEMPTING TO TOUCH DOWN, AT ABOUT 5' ABOVE THE RWY, WE ENCOUNTERED AN EXCESSIVE DOWNDRAFT WHICH RESULTED IN A HARD LNDG. IN OUR OPINION, A GO-AROUND IN THIS POSITION WAS NOT AN OPTION, SINCE CLOSE PROX TO THE RWY AND LOW AIRSPEED WOULD HAVE COMPLICATED THE SITUATION. ALSO, AN ENCOUNTER WITH THE MENTIONED DOWNDRAFT AT A HIGHER ALT THAN MENTIONED (5') WITH A GO-AROUND ATTEMPT WOULD MOST LIKELY HAVE RESULTED IN A MUCH HARDER CONTACT WITH THE RWY THAN EXPERIENCED. OUR COMPANY WAS ADVISED OF THE MISHAP, AND NO INJURIES OCCURRED.

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.