Pinnacle Airlines Flight 3701

From Wikipedia, the free encyclopedia

**Pinnacle Airlines Flight 3701**
Summary
Date	October 14, 2004
Type	Engine Flameout, Pilot error
Site	Jefferson City, Missouri
Passengers	0
Crew	2
Injuries	0
Fatalities	2
Survivors	0
Aircraft type	Bombardier CRJ-200
Operator	Pinnacle Airlines
Tail number	N8396A

Pinnacle Airlines Flight 3701 (ICAO: FLG3701, IATA: 9E3701, or Flagship 3701) crashed on October 14, 2004, near Jefferson City, Missouri. It was an overnight ferry flight (with no passengers) from Little Rock, Arkansas to Minneapolis, Minnesota. Both crew members were killed.

1 The accident
2 Why the plane was empty
3 Investigation
4 Aftermath
5 References
6 External links

[edit] The accident

Pinnacle Airlines (operating under the Northwest Airlink banner) Flight 3701 was an empty 50-seat Bombardier CRJ-200 (CL-600-2B19), N8396A, on ferry from Little Rock, Arkansas (Little Rock National Airport) to Minneapolis, Minnesota (Minneapolis-St. Paul International Airport), manned by two pilots, Captain Jesse Rhodes and First Officer Peter Cesarz. The jet crashed when the engines could not be restarted and they could not glide to an airport. There were no casualties on the ground.

Both pilots were trained at Gulfstream Academy in Florida, eventually hired on with Pinnacle Airlines after their time spent with Gulfstream International Airlines.

[edit] Why the plane was empty

Due to urgent but routine maintenance, the aircraft was unavailable for a scheduled flight earlier in the day. As do many airlines, Pinnacle had a spare aircraft available, which it used. The aircraft involved in the accident was then required at Minneapolis-St. Paul International Airport, where it would have been had it undertaken its originally scheduled flight. For this reason it was necessary to ferry the aircraft to Minneapolis in an empty state.

[edit] Investigation

The investigation into the accident focused mainly on information contained on the flight data recorder and the cockpit voice recorder. This is the official version of events as determined by that investigation.

The two pilots were exploiting the performance of the empty CRJ-200 on the ferry flight. The pilots decided to test the limits of the CRJ, and join the "410 Club," referring to pilots who pushed CRJs to their maximum approved altitude of Flight Level 410 (41,000 feet).

The incident started when the pilots performed several non-standard maneuvers at 15,000 feet, including a pitch-up at 2.3g (23 m/s²) that induced a stall warning. They set the autopilot to climb at 500 ft/min to FL410. This exceeded the manufacturer's recommended climb rate at altitudes above FL380. In the attempt to reach FL410, the plane was pushed at over 1.2g, and the angle of attack became excessive to maintain climb rate in the thinner upper atmosphere. After reaching FL410, the plane was cruising at 150 knots (280 km/h), barely above stall speed, and had over-stressed the engines. The anti-stall devices activated while they were at altitude, but the pilots overrode the automatic nose-down that would increase speed to prevent stall. After four overrides, both engines experienced flameout and shut down. The plane then stalled, and the pilots recovered from the stall at FL380 while still having no engines. This led the pilots to pitch nose down in an attempt to restart the engines. The crew failed to dive sharply enough to attain the required 300 kt for a windmill restart, ending the dive when they had reached 230 kt. Since they were too high for an APU start, the ram air turbine (known as an Air Driven Generator on Bombardier products) was deployed to power the aircraft, and the crew donned oxygen masks as the cabin slowly depressurized due to loss of pressurization air from the engines. The crew glided for several minutes. The crew then tried to restart engines using the APU at 13,000 ft. This was again unsuccessful. They then declared to Air Traffic Control (ATC) that they had a single engine flameout. At this point they had 4 diversion airports available to them. As attempts to restart the engines continued to fail, they declared to ATC that they had in fact lost both engines, leaving only two possible emergency airports.

They crashed outside Jefferson City, Missouri, behind a row of houses (the 600 block of Hutton Lane — roughly two miles from Jefferson City Memorial Airport), and the plane caught fire, killing both pilots. No one on the ground was hurt.

[edit] Aftermath

Pinnacle Airlines has restricted flights to a maximum of FL370. It has also changed its training program to include high altitude operations in ground school and simulator training. In addition, each crew is taken in the simulator up to FL410 and shown what the airplane did on the night Flight 3701 crashed.

The National Transportation Safety Board has determined from the Flight Data Recorder that the turbofan jet engines (General Electric CF34-3B1) engine 2 turbine was operating at 300 °C above the maximum redline temperature of 900 °C at 41,000 ft. Engine 1 HPT stayed 100 °C below the redline.

[edit] References

"We don't have any engines", (Jim Gorman), Popular Mechanics, Hearst Communications, New York, New York, USA, January 2006, Volume 138, Number 1, pp.40-42
NTSB Accident Information Brief Update for October 29, 2004 (PDF)