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Aloha Airlines flight 234 lifted off from Hilo airport on the main island of Hawaii just before 1:30pm bound for Honolulu, the company's base. Captaining the flight that day, April 28, 1988, was Robert Schornstheimer and First Officer Madeline Tomkins, who was at the controls during that leg. Also on board the 737 that afternoon were three cabin crew members and eighty-nine passengers. 234 reached it's cruising altitude of FL240 twenty minutes into the flight, while passing abeam the north-western tip of the island. Just after levelling off, there was a loud explosion followed by screaming and debris filling the cockpit and cabin. The Captain quickly took the controls and both flight crew members donned their oxygen masks. Looking back, the flight crew could see that the cockpit door had been torn off and they could see blue sky through the hole.

Passengers Scramble to Exit 243

Though the aircraft seemed somewhat unstable, it was responding to control and the Captain immediately began an emergency descent towards Kahului airport on the island of Maui. First Officer Tompkins began calling ATC to report the diversion and emergency, but because of the noise, she could not hear any reply. As they were approaching Kahului, Tompkins switched over to the tower frequency and was able to make contact. The tower then mobilized emergency equipment. 243 continued to approach from the south and through the controls were still sluggish, the aircraft was flying well and had been slowed to approach speed.

The gear was selected down and though the main gear down position light illuminated, the nose gear did not. Tompkins selected the manual extension and though the nose gear light did not illuminate, the gear unsafe light did go out. The crew was then under the impression that they would be landing without the nose gear. Having lined up with the runway with flaps at the 5 position, the Captain then asked for flaps 15, which caused the aircraft to become markedly less controllable. Tompkins then retracted the flaps back to 5 and consulted the flight manual for the new Vref speed, which she determined to be 152kts.

Upon slowing through 170kts, however, the captain found the aircraft to again become uncontrollable, so it was decided to land at 170kts. The tower then called 243 and reported that it looked as if all gear were in the down position. As the Captain advanced the throttles to keep up the speed, he found that the port engine had failed. He attempted to restart it, but to no avail. Powered by the only remaining engine, 243 touched down smoothly on runway 2 and braked to a stop, the nose gear holding up throughout the touchdown. The crew quickly opened up the aircraft and was able to evacuate the passengers. It was only then that they realized that flight attendant Clarabelle Lansing had been ejected from the aircraft during the explosive decompression. Fortunately, though many other passengers were injured, some severely, everyone else survived.

It was obvious that 243 suffered a devastating explosive compression, tearing off a section of the forward fuselage 18 feet long from the port floor level to the starboard floor level. The leading edges of both wings and tail fins showed denting from debris impact. The engine cowls and first stage fan blades showed impact damage as well. Debris had lodged in the leading edge of the starboard wing near the engine pylon. This prevented the slat from extending, causing the control difficulties when the crew attempted to configure for landing. Broken starter and power lever cables which ran through the leading edge of the port wing were broken, which caused the loss of the port engine. The nose gear light bulb had burnt out.

Debris Jammed in Slats Near Engine

A passenger later recalled that upon boarding the aircraft at Hilo, she had noticed a crack in the fuselage running through a row of rivets just aft of the door. She did not mention it to the crew, believing that they would not take her seriously. The aircraft involved in the accident was 19 years old, having begun service with Aloha in 1969. In fact, the aircraft had completed 89,680 flight cycles, the second highest number in the entire worldwide fleet of 737 aircraft. However, because most Aloha flights were of short duration, the maximum cabin pressure differential was not always reached so the equivalent number of cycles was significantly less. The aircraft had been involved in one other incident involving clear air turbulence, but no structural damage was recorded. In the early production of the 737, including the aircraft involved in the accident, Boeing used a cold bonding procedure to join fuselage skin joints.

However, this technique was discontinued due to possible corrosion if moisture was allowed into the bond. Examination of the several pieces of the aircraft's skin showed many fatigue cracks along joining rivets as well as moderate corrosion along most of the joints. One joint had disbonded completely. Investigators concluded that the skin separation began near floor level on the port side at about row 3. Investigators found that, because of Aloho's high flight cycles, it's inspection schedule was not sufficient for detection of fatigue cracking.