Synopsis
The aircraft departed Weston (EIWT) at approximately 13:10 UTC to practice instrument approaches at Ireland West Airport Knock (EIKN). The pilot flew a manual instrument approach in instrument meteorological conditions, followed by an overshoot. During the overshoot at about 1,800 ft, the aircraft rolled to the right in excess of 90°. The non-flying pilot took control, initially attempted recovery, then continued the roll through 360°. With high power and an inverted nose-down attitude, altitude was lost and speed increased rapidly. Recovery involved gross over-speed and high G loading to avoid ground contact. The flight returned to EIWT and landed safely. No injuries occurred. The aircraft sustained distortion to wings and tailplane.
History of the Flight
The flight was operated with the beneficial owner as pilot-flying (PF) in the left seat, accompanied by a pilot-non-flying (PNF) in the right seat. Both held FAA licences and instrument ratings. The purpose was to practice instrument procedures using a Garmin GNS 530 navigation system, with which the PF was not particularly familiar. A VFR flight plan was filed with ATC Shannon, stating "Calibration of aircraft". Weather at EIKN deteriorated progressively. On initial contact, they were cleared to descend to 3,000 ft and self-position for an ILS approach to Runway 27. After another aircraft reported cloud base at 180 ft, they stated they would not land but were trying to calibrate an ILS on the Garmin 530. They were cleared to establish on the localiser, reported established at 3,000 ft, and requested a go-around with vectors for another ILS. ATC informed them of no radar and cleared them for a go-around with a right turn to the OK beacon for an NDB/ILS approach. They accepted and stated they would break off the approach at 600-700 ft above the airport.
At 15:37:22 they reported on the go-around. At 15:39:59 ATC requested altitude. Seven seconds later they responded that they were having trouble. When queried, they responded "Hold on…". At 15:41:08 they reported trouble with the GPS and were level at 3,500 ft heading north. They later stated they were returning to EIWT. The flight back was uneventful. After landing, they did not notice damage; the PF was informed later by his mechanic. Over a month later, an IAA inspector discovered the damage and notified the AAIU. The PF reported that the incident was turbulence related.
Damage to Aircraft
Inspection revealed buckled skin on the top wing surface of both wings at the outer panel joint, with ripples extending outboard. Wrinkles were found on the top and lower stub wing, particularly near the port wing root/fillet intersection. The top surface of the port tailplane showed distortion near its root. Raytheon Aircraft Company stated the damage was representative of excessive G and over-speed, estimating at least 4.5 G. They indicated probable twisting of horizontal stabilizers.
Personnel Information
The PF, aged 48, held an FAA Private Pilot's Licence with Instrument Rating, but his FAA medical certificate was not valid as it was issued by an IAA approved examiner not approved by FAA. The PF claimed unawareness. The PNF, aged 41, held a valid FAA Commercial Pilot's Licence with Instrument Rating, with about 2,000 hours on multi-engine, aerobatic aircraft, and was familiar with the GNS 530.
Pilot Statements
In interview, the PF stated he disconnected the autopilot and manually flew the approach to about 1,400 ft, then executed a go-around. At about 1,800 ft, they experienced a sudden jolt and the aircraft rolled right, unresponsive to left aileron. The PNF took control. The PF did not remember negative G but was aware of proximity to ground. He had not done aerobatics and did not know the G forces. He stated the incident was probably turbulence related.
The PNF stated he was examining an approach chart when he looked up and saw bank angle over 90° with accelerating roll rate. He grabbed controls, initially tried recovery with left aileron without effect, then decided to continue the roll through 360°. With high power and nose down, altitude was lost and speed rose. He recovered with high G loading.