Wrong approach speeds used for approach and landing. A hard landing results.

Attributes
ACN	315271
Time
Date	199509
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : gso
State Reference	NC
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tower : gso
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	landing other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : instrument pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 0 flight time total : 3500 flight time type : 0
ASRS Report	315271
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : far other anomaly other
Independent Detector	other flight crewa
Resolutory Action	other other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Our flight was from roa to gso, a very short flight of only 70 NM. At our company, we use a laptop computer to figure our landing speeds. To do this, we must input our estimated landing weight into the computer. The estimated landing weight is found by subtracting our projected fuel burn from our takeoff gross weight. While enroute, we were in a hurry and subtracted the projected fuel burn from the zero fuel weight instead of the takeoff gross weight. As a result of this mistake, the computer gave us landing speeds that were 10 to 12 KTS slower than what we should have had. Our actual landing weight was around 140000 pounds but I input 123000 pounds in the laptop (which gave us the slower speeds). As a result of the slower speeds, the captain made a hard landing. After the hard bounce, he elected to do a go around. He was puzzled as to why the landing was so hard. On the go around, I figured out what happened and re-figured the correct speeds for an uneventful second landing. Factors causing mistake. Short flight, in too big of a hurry. Did not double check speed. New crew, none of us had flown in a few days.

Original NASA ASRS Text

Title: WRONG APCH SPDS USED FOR APCH AND LNDG. A HARD LNDG RESULTS.

Narrative: OUR FLT WAS FROM ROA TO GSO, A VERY SHORT FLT OF ONLY 70 NM. AT OUR COMPANY, WE USE A LAPTOP COMPUTER TO FIGURE OUR LNDG SPDS. TO DO THIS, WE MUST INPUT OUR ESTIMATED LNDG WT INTO THE COMPUTER. THE ESTIMATED LNDG WT IS FOUND BY SUBTRACTING OUR PROJECTED FUEL BURN FROM OUR TKOF GROSS WT. WHILE ENROUTE, WE WERE IN A HURRY AND SUBTRACTED THE PROJECTED FUEL BURN FROM THE ZERO FUEL WT INSTEAD OF THE TKOF GROSS WT. AS A RESULT OF THIS MISTAKE, THE COMPUTER GAVE US LNDG SPDS THAT WERE 10 TO 12 KTS SLOWER THAN WHAT WE SHOULD HAVE HAD. OUR ACTUAL LNDG WT WAS AROUND 140000 LBS BUT I INPUT 123000 LBS IN THE LAPTOP (WHICH GAVE US THE SLOWER SPDS). AS A RESULT OF THE SLOWER SPDS, THE CAPT MADE A HARD LNDG. AFTER THE HARD BOUNCE, HE ELECTED TO DO A GAR. HE WAS PUZZLED AS TO WHY THE LNDG WAS SO HARD. ON THE GAR, I FIGURED OUT WHAT HAPPENED AND RE-FIGURED THE CORRECT SPDS FOR AN UNEVENTFUL SECOND LNDG. FACTORS CAUSING MISTAKE. SHORT FLT, IN TOO BIG OF A HURRY. DID NOT DOUBLE CHK SPD. NEW CREW, NONE OF US HAD FLOWN IN A FEW DAYS.

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.