Accident McDonnell Douglas DC-9-31 N964VJ,

ASN Wikibase Occurrence # 327418

Date:	Wednesday 13 June 1984
Time:	16:56
Type:	McDonnell Douglas DC-9-31
Owner/operator:	USAir
Registration:	N964VJ
MSN:	47373/522
Year of manufacture:	1969
Engine model:	Pratt & Whitney JT8D-7B
Fatalities:	Fatalities: 0 / Occupants: 56
Aircraft damage:	Substantial, repaired
Category:	Accident
Location:	Detroit-Metropolitan Wayne County Airport, MI (DTW) - United States of America
Phase:	Landing
Nature:	Passenger - Scheduled
Departure airport:	Hartford-Brainard Airport, CT (HFD/KHFD)
Destination airport:	Detroit-Metropolitan Wayne County Airport, MI (DTW/KDTW)
Investigating agency:	NTSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
A McDonnell Douglas DC-9-31 operated by USAir, suffered a landing accident at Detroit-Metropolitan Airport, MI.
During arrival, the aircrew noted thunderstorms west & southwest of the airport. The crew elected to continue and make an ILS approach. At 16:36, a special weather observation had thunderstorm info, but was not noted. At 16:50, the visibility dropped to 1/4 mi with heavy rain and hail. As the aircraft approached runway 21R, a VIP Level 4 thunderstorm moved from west to east over the northern part of the airport. The controller provided wind info from the low level wind shear alert system (LLWAS), but used improper phraseology and failed to provide RVR information when the visibility went below 1 mile. The crew had difficulty in understanding the LLWAS info due to the amount and rapidity that it was provided. At approx 350 feet agl, the aircraft encountered low clouds, heavy rain, hail and turbulence. The aircrew initiated a missed approach. The speed increased to 143 kts, then decreased to approx 119 kts. The captain believed the aircraft would not climb and elected to land. The aircraft touched down about 2500 feet down the runway with the gear partially extended, then slid 3800 feet and went off the runway. The wind was gusting to 32 kts.

Probable Cause: "Inadequate cockpit coordination and management which resulted in the captain's inappropriate decision to continue the instrument approach into known thunderstorm activity where the airplane encountered severe wind shear. The failure of air traffic control personnel at the airport to provide additional available weather information deprived the flightcrew of information which may have enhanced their decisionmaking process."

Accident investigation: