Runway excursion, loss of aircraft control.

Attributes
ACN	94587
Time
Date	198809
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : atl
State Reference	GA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : spi
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	landing other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 10000 flight time type : 7500
ASRS Report	94587
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : flight engineer pilot : commercial
Experience	flight time last 90 days : 150 flight time total : 10000 flight time type : 700
ASRS Report	94578
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : regained aircraft control
Consequence	other Other
Supplementary
Primary Problem	Weather
Air Traffic Incident	other

Narrative:

During the flair on landing unexpected rain reduced our visibility to 0. Aircraft hydroplaned off the left side of runway. After about 1500' we could see enough to return to the runway. Visibility was good during approach and fair on the rollout end. What was unusual about this is the small area of very heavy rain in the T/D zone. We were landing on runway 27L and during the approach you could see the full length of runways 26L and right, which deceived us as to how hard the rain was on runway 27L. Callback conversation with reporter revealed the following: reporter states extremely unusual conditions. A line of isolated small cells existed diagonally across the airport. Aircraft had descended through area anticipating gusts and instead encountered fairly smooth air. On approach could see the airport for 10 mi. Aircraft in trail landing ahead had no problems. Reporter's aircraft flared at moment when rain became extremely heavy cutting visibility to 0 for out 2000'. 12 KT crosswind must have been much greater within the rain area. With 0 visibility crew could not know there was a need for more correction. Atl is known for standing water on runway. Tower had no way to know intensity of the rain to give warning. Left main wheel only was off runway.

Original NASA ASRS Text

Title: RWY EXCURSION, LOSS OF ACFT CONTROL.

Narrative: DURING THE FLAIR ON LNDG UNEXPECTED RAIN REDUCED OUR VIS TO 0. ACFT HYDROPLANED OFF THE LEFT SIDE OF RWY. AFTER ABOUT 1500' WE COULD SEE ENOUGH TO RETURN TO THE RWY. VIS WAS GOOD DURING APCH AND FAIR ON THE ROLLOUT END. WHAT WAS UNUSUAL ABOUT THIS IS THE SMALL AREA OF VERY HEAVY RAIN IN THE T/D ZONE. WE WERE LNDG ON RWY 27L AND DURING THE APCH YOU COULD SEE THE FULL LENGTH OF RWYS 26L AND R, WHICH DECEIVED US AS TO HOW HARD THE RAIN WAS ON RWY 27L. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR STATES EXTREMELY UNUSUAL CONDITIONS. A LINE OF ISOLATED SMALL CELLS EXISTED DIAGONALLY ACROSS THE ARPT. ACFT HAD DSNDED THROUGH AREA ANTICIPATING GUSTS AND INSTEAD ENCOUNTERED FAIRLY SMOOTH AIR. ON APCH COULD SEE THE ARPT FOR 10 MI. ACFT IN TRAIL LNDG AHEAD HAD NO PROBS. RPTR'S ACFT FLARED AT MOMENT WHEN RAIN BECAME EXTREMELY HEAVY CUTTING VIS TO 0 FOR OUT 2000'. 12 KT XWIND MUST HAVE BEEN MUCH GREATER WITHIN THE RAIN AREA. WITH 0 VIS CREW COULD NOT KNOW THERE WAS A NEED FOR MORE CORRECTION. ATL IS KNOWN FOR STANDING WATER ON RWY. TWR HAD NO WAY TO KNOW INTENSITY OF THE RAIN TO GIVE WARNING. LEFT MAIN WHEEL ONLY WAS OFF RWY.

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.