Learjet 23

Government of the State of Tlaxcala

The crew departed Puebla-Hermanos Serdán-Huejotzingo Airport on a positioning flight to Atlangatepec. On approach to runway 01, the crew made a low pass over the runway then initiated a go-around procedure followed by a circuit in an attempt to land on runway 19. On final approach in limited visibility due to the night and low clouds, the aircraft impacted the water surface and crashed in the Atlanga lagoon. The aircraft sank by a depth of about 30 metres some 800 metres short of runway threshold. Both pilots were killed.

Sierra West Airlines

On March 4, 1998, at 1350 hours Pacific standard time, a Learjet 23, N37BL, was substantially damaged when it landed gear up at the Oakdale, California, airport. The airline transport pilot and check pilot, the sole occupants, were not injured and no property damage occurred. The flight was operating under 14 CFR Part 91 on a familiarization and training flight. Visual meteorological conditions prevailed and no flight plan was filed. The pilot stated in his report "the landing gear was never extended and the aircraft was landed with the gear retracted."

Jetstream International Inc.

A lineman noted parking brake (p/b) was set before flight. Pilots began takeoff on 5,147 feet runway with 10 knots crosswind. A witness said aircraft rotated for takeoff about 4,500 feet down runway and lifted off about 50 feet later. Reportedly, it remained low and slow (20-60 feet agl) after lift-off, then banked (rocked) left and right in nose high attitude, settled, hit trees and crashed abt 200 feet beyond runway. One person said aircraft went out of control before impact; another said it was 'in or on the edge of stalled flight.' Examination showed rotational damage occurred in both engines during impact. The braking systems had evidence that p/b control valve was partially on; brake torque tube contained heat blueing. On this early model (Learjet 23/sn: 23-45a), p/b had to be released by depressing brake pedals first; pilot handbook did not address this. On later models (sn: 23-050 and up), p/b needed only to be moved 'off.' Investigations showed left seat pilot had training in later models (Learjet 24/25); but only a biennial flight review was noted in the model 23. Company dispatcher said no training would have been performed on accident flight (with passenger aboard). Aircraft was about 430 lbs over max weight limit. All three occupants were killed.

Kalitta Charters - Kalitta Services

The pilot had computed landing performance information for a landing on a wet runway with anti-skid; sufficient runway surface was available. Touchdown was normal, however during the braking process, the airplane started to fishtail and the pilot believed that the anti-skid system had failed. Therefore, the pilot turned the antiskid system off and continued the rollout with normal braking. The airplane went off the departure end of runway 05 and sustained substantial damage. Performance data indicated more runway surface was required for a safe landing on a wet runway without anti-skid assistance. The braking sequence of events described by the pilot resembled dynamic hydroplaning where there was a complete loss of braking effectiveness rather than an anti-skid malfunction. An examination of the airplane failed to disclose any mechanical problems.

Aeroflight Services

At 0515 est, the flight was cleared for takeoff on a flight from Ypsilanti, MI to Louisville, KY. About 17 minutes later, the flight crew began to display indications of a deterioration of their ability to control the aircraft. At 1st, they deviated from instruments to hold west of the Findlay VOR at FL220. As the flight continued and was cleared to FL270, the crew displayed confusion about magnetic headings and basic instruments. At 1048 est, the aircraft deviated from the en route heading and the wrong heading was read back after a heading correction was given. Also, the aircraft continued climbing (to FL291), then radar and radio contact were lost at 0551 est. The controller noted the pilot's speech was slurred and some portions of the conversation were unintelligible. Subsequently, the aircraft crashed in a steep dive. No preimpact part failure was verified, though impact forces and post-crash fire resulted in extensive damage of the aircraft. The aircraft was equipped with oxygen and pressurization system. No audible warning was noted on ATC recordings to indicate the cabin altitude had exceeded 10,000 feet, though the aircraft was equipped with such a device. Both pilots were killed.

Air Entreprise

For unknown reasons, the twin engine aircraft belly landed at Lisbon-Portela de Sacavém Airport and slid for few dozen meters before coming to rest. Both pilots were uninjured while the aircraft was damaged beyond repair.

Jet Management - USA

After landing at the aircraft's manufacturer facility with an asymmetric fuel condition and an inoperative yaw damper the crew elected to continue the flight to their destination without correcting the deficiencies. Enroute the captain informed air traffic controllers that he had fuel coming from one tank and that he doubted that had fuel available to reach his destination. The controller cleared the aircraft to land at a March AFB, the nearby airport. As the aircraft turned onto the final approach it rolled inverted and impacted the ground inverted short of runway 32. Both pilots were killed.

Dolphin Aviation

On approach to Guatemala City-La Aurora Airport, the crew encountered poor weather conditions and limited visibility. It is believed he also encountered engine problems when the aircraft struck tree tops and crashed few km short of runway. A crew member was rescued while two other occupants were killed. The flight was operated on behalf of DHL Airways.

Air Continental

On June 4, 1984, an unmodified Gates Learjet 23A, N101PP, was being operated by Air Continental, Inc., Elyria, Ohio, on a regularly scheduled cargo flight transporting cancelled bank checks under 14 CFR 135. The flight departed Cleveland-Hopkins International Airport, Ohio, as Night Air 4 at 2200 eastern daylight time. After an uneventful flight, Night Air 4 arrived at Syracuse-Hancock International Airport, New York, at 2245. There was routine ground cargo handling at Syracuse; the airplane was not refueled. Night Air 4 departed Syracuse at 2311, was cleared to climb to 17,000 feet, and was handed off to Boston Air Route Traffic Control Center (Boston Center) at 2314. Boston Center cleared Night Air 4 to its requested altitude of FL290 and the en route portion of the flight was uneventful. At 2332, Night Air 4 was handed off at 16,000 feet during its descent to Bradley International Airport, Windsor Locks, Connecticut Approach Control. Approach control identified the airplane, cleared it for a visual approach to runway 33, and at 2336 gave Night Air 4 a turn to position the airplane on final approach at 10 miles from the airport. At 2338:22, Night Air 4 reported that the airplane was on final approach for runway 33, and at 2338:25 the air traffic control tower operator cleared the flight to land. At 2341:18, the control tower operator reported to approach control that there had been an accident at the airport. Fifteen witnesses, who either heard and/or saw the accident, were interviewed, and with the exception of a few minor points, all of the witnesses described basically the same accident sequence. The airplane was on a normal approach to runway 33 with no apparent abnormalities. When the airplane was about 200 feet over the approach lights, an increase in engine thrust was heard and the airplane halted its rate of descent in what two pilot witnesses thought was an apparent attempt to go-around. Immediately afterward, Night Air 4 began what appeared to be a level turn to the right. As the airplane went through about 90° of turn, the wings of the aircraft were nearly vertical to the ground. The airplane's nose dropped below the horizon and the airplane descended into the ground in a nose low attitude. The witnesses stated that they saw an explosion which was followed by intense ground fire. None of the witnesses reported any significant lateral or vertical changes while the aircraft was on short final or during the 90' right turn prior to its descent into the ground. Many witnesses stated that they saw some lights illuminated on the aircraft but none reported seeing the landing lights, located on the landing gear, or the landing gear in the extended position. Witnesses reported no inflight fire, smoke, or airframe separation before the crash. All three occupants were killed.

Ibex Corporation

While in cruise flight on Airway J79-121 en route to Orlando, Florida, from Teterboro, New Jersey, the flightcrew of N100TA, an IBEX Corporation Gates Learjet 23, was cleared by the Jacksonville Air Route Traffic Control Center to descend from its altitude of Flight Level 410 to Flight Level 390. The flightcrew acknowledged the clearance, and air traffic control observed the radar target descend. About 2 minutes later, the airplane crashed into the Atlantic Ocean, from a steep, high-speed descent about 12 miles from Savannah, Georgia. The air traffic controller made several unsuccessful attempts to contact the airplane. The pilots had reported no difficulties in any of their radio transmissions. The pilot, copilot, and the two passengers on board were killed. Beyond 1158:49, the program showed a gradual increase in indicated airspeed from 271 to 400 KIAS. The average rate of descent was 15,375 fpm based on the radar data using pressure altitude (mode C).