N112EMIsrael Aircraft Industries 1125 WESTWIND ASTRA · 1988

On June 18, 2013, about 1125 eastern daylight time, an Israel Aircraft Industries (IAI) 1124 airplane, N112EM, was substantially damaged following a landing gear collapse at Cincinnati Municipal Airport (KLUK), Cincinnati, Ohio. The flight instructor, pilot, and pilot-rated passenger did not report any injuries. The airplane was registered to and operated by E. Micah Aviation Incorporated under the provisions of 14 Code of Federal Regulations Part 91 as an instructional flight. Day visual meteorological conditions prevailed and no flight plan was filed. The local flight departed KLUK about 1045.

According to the cockpit voice recorder (CVR), the pilot and flight instructor briefed an instrument landing system (ILS) approach to runway 21L at KLUK. The flight instructor requested two ILS approaches from air traffic control (ATC) and was given missed approach instructions. After contacting the KLUK control tower, the flight instructor requested and received clearance for the "option", which permits a touch-and-go, low approach, missed approach, stop-and-go, or full stop landing.

The flight instructor verbally coached the student throughout the instrument approach, flare and landing. Although the student had flown more than 3,600 total flight hours, he was attempting his first landing in this airplane type and had not landed a high-performance or turbine powered airplane in several years.

As the pilot was flaring the airplane to land, the CVR recorded a steady tone with the frequency of the 'trim movement' buzzer, which continued 8.5 seconds. Immediately after the airplane touched down, the flight instructor stated "no, no, no, we're not stopping". As the flight instructor was making this statement, at 1125:00, a half-second rumbling sound was recorded and the trim movement buzzer tone stopped. One second later, the student stated "okay, my bad". A half second later, at 1125:01.5, the CVR recorded a steady tone with the frequency of the gear warning horn, which continued until the end of the recording. At 1125:03, a 'thunk' sound was recorded, followed by a scraping noise. At 1125:07, the scraping noise restarted and continued for about 20 seconds. The background sound and scraping noise decreased in intensity over the 20 second period, similar to the airplane decelerating.

The airplane came to a stop near the end of runway 21L with the left landing gear collapsed outward, since the IAI 1124 landing gear normally retracts outward. The airplane was hoisted up by airport personnel for recovery. While being raised, the left landing gear dropped, by gravity force alone, from a retracted position to a 'down and locked' position. No damage was observed to the left landing gear or its brace assemblies. Scrape damage consistent with runway contact was observed on the underside of the right wing, near the wingtip. Substantial damage had occurred to structural areas of the fuselage.

The flight instructor stated that the airplane never lifted off the ground during the touch-and-go sequence and thought a mechanical failure of the landing gear had occurred. The pilot was unsure of the sequence of events and stated that the flight instructor seemed to be rushing the touch-and-go sequence, as he perceived that ample runway and time existed to accelerate further prior to takeoff rotation. Neither the flight instructor nor pilot recalled moving the landing gear handle during the touch-and-go sequence.

A pilot-rated passenger, who was seated aft of the pilot and flight instructor, stated that the landing was normal. When he heard the flight instructor's command to continue with a touch-and-go, he leaned back in his seat and no longer had a view into the cockpit area. The passenger observed the airplane become airborne for one or two seconds. While airborne, the airplane banked to the right and the right wing tip contacted the runway. The airplane subsequently yawed left and the left landing gear collapsed as the airplane contacted the runway. The passenger did not notice if the landing gear selector handle was moved during the touch-and-go sequence.

A maintenance worker located at the departure end of the runway observed the airplane land normally, followed by a bank to the right and strike of the right wingtip. He then noticed the airplane yaw to the left and the left landing gear collapsed.

Federal Aviation Administration (FAA) personnel examined and tested the landing gear. The landing gear hydraulically retracted 'outward' into the strut and wheel well, under the wing. The gear was locked in the 'up' position by means of a lock assembly located in each wheel well. In the 'down' position, the gear was locked and braced by side and jury brace assemblies.

The airplane was placed on jacks and the landing gear was cycled several times, with no anomalies noted. No damage was observed to the landing gear or brace assemblies. The FAA conducted a second test of the landing gear to examine adjustment criteria called out in the IAI 1124 maintenance manual. The landing gear was again cycled several times, with no anomalies noted. The clearance was checked between the piston plunger end of the landing gear unlock cylinder and unlock tang on back of the upper jury brace. This measurement was correct, which ensured that the piston travel was correct.

A review of manufacturer records and NTSB accident data did not reveal any similar landing gear incidents or accidents for IAI 1124 aircraft. The manufacturer stated that jury and/or side brace damage would be evident if the landing gear was down and locked during a collapse sequence.