Accident Gulfstream G-V-SP (G550) N535GA,

ASN Wikibase Occurrence # 321170

Date:	Monday 14 February 2011
Time:	13:15
Type:	Gulfstream G-V-SP (G550)
Owner/operator:	Gulfstream Aerospace
Registration:	N535GA
MSN:	5305
Year of manufacture:	2010
Total airframe hrs:	10 hours
Engine model:	Rolls-Royce BR700-710C4-11
Fatalities:	Fatalities: 0 / Occupants: 3
Aircraft damage:	Substantial, repaired
Category:	Accident
Location:	Appleton-Outagamie County Airport, WI (ATW) - United States of America
Phase:	Landing
Nature:	Test
Departure airport:	Appleton-Outagamie County Airport, WI (ATW/KATW)
Destination airport:	Appleton-Outagamie County Airport, WI (ATW/KATW)
Investigating agency:	NTSB
Confidence Rating:	Accident investigation report completed and information captured

Narrative:
A Gulfstream Aerospace GV-SP airplane, N535GA, had a landing overrun on runway 30 (6,501 feet by 150 feet, dry grooved concrete) at the Appleton-Outagamie County Regional Airport (ATW), Wisconsin, following a reported loss of a hydraulic system. The airplane incurred substantial left wing damage when the left main landing gear collapsed during the overrun.
The purpose of the flight was a test flight following the installation of the airplane's interior prior to delivery of the airplane to its owner. The flight departed from Appleton about 10:10. The flight returned about three hours later.
While the airplane was inside the final approach fix, an amber left side hydraulic quantity low crew alerting system (CAS) message illuminated. The pilot flying (PF) noticed the hydraulic fluid quantity decreasing. Subsequently, an amber left hydraulic system fail CAS message appeared. The pilot not flying (PNF) pulled out the checklist to accomplish the left hydraulic system failure procedures and then suggested a go-around because the landing runway was about 500 feet shorter than the recommended minimum runway length indicated in the checklist. The PF decided to land due to the hydraulic quantity indications, prior autopilot problems, and the airplane's landing configuration. The PNF turned on the auxiliary pump about 500 feet above ground level, and both the PF and PNF thought the auxiliary hydraulic system could support normal spoilers, brakes, and nosewheel steering. The PF selected right thrust reverser aft and began pressing the brakes, but he felt no braking action. He reached for the emergency brakes; however, he did not immediately apply them to slow the airplane because he decided that there was not enough distance remaining to stop the airplane on the runway. Therefore, he attempted to go around with insufficient runway remaining by advancing the throttles to the maximum continuous thrust setting. The PNF did not see the airspeed increase and believed that not enough runway remained to get airborne, so he pulled the throttles back to avoid a runway overrun. The airplane exited the runway and sustained substantial damage. A review of the cockpit voice recorder transcript indicated that, before the emergency, the flight crew did not maintain a disciplined cockpit environment that focused on operationally relevant discussion but instead repeatedly made reference to and discussed objects on the ground and other operationally irrelevant topics. The lack of a sterile cockpit did not promote crew coordination and communication and adherence to procedures, which would have helped mitigate this emergency.

PROBABLE CAUSE: "The pilot flying's (PF) decision to land on a shorter-than-recommended runway with a known left hydraulic system failure rather than go around as suggested by the pilot-not-flying, his failure to immediately apply emergency brakes following the detection of the lack of normal brakes, and his attempt to go around late in the landing roll with insufficient runway remaining. Contributing to the accident was the nose landing gear swivel assembly failure, the lack of a hydraulic fuse before this critical failure point, and the design of the swivel using two similar alloys with a propensity to adhere to each other when rubbed together. Also contributing to the accident was the lack of a disciplined cockpit environment."

Accident investigation: