Kapar airplane crash the result of ‘departure from controlled flight’

Did the Blackshape Gabriel BK160TR aircraft that crashed on Feb 13 in Kapar, killing two on board, suffer a ‘departure from controlled flight’?

Former airline captain Datuk Nik Ahmad Huzlan Nik Hussain said that from the video footage of the falling debris, it would appear that the aircraft suffered a structural failure, and broke apart in mid-air.

“Of course, right now it’s pure conjecture because we don’t know what happened, or how it happened, but if you’re asking me if a departure from controlled flight could cause the aircraft to break apart, then, yes… it is possible,” said Nik Ahmad Huzlan.

“From the video, you can see the lightweight parts that detached from the aircraft drifting down. These are possibly lifting surfaces. So yeah, it looks like a structural failure. Maybe a wing failure, or the spar broke, or just a catastrophic detachment of the lifting panels.”

On Feb 13, an Italian-made Blackshape Gabriel BK160TR (registration I-POOC) crashed in Kampung Tok Muda, Kapar, Klang.

The crash killed two men on board – Daniel Yee Hsiang Khoon, 30, and Roshaan Singh Rania, 42.

CAAM’s chief executive officer, Captain Datuk Norazman Mahmud told Twentytwo13 that the flight plan filed by the flight crew was for a ‘recreational’ sortie, not a training flight.

“A departure from controlled flight could result in structural failure. By the same token, a structural failure could also lead to a departure from controlled flight. Over-exertion of control surfaces can cause wing warping, resulting in popped rivets or fasteners of panels.

“Too much pitch load manoeuvers can also cause structural failure. If we’re talking about aerobatics on this aircraft, I would think that it’s only limited to ‘soft’ aileron rolls or low-G loops, similar to the Cessna 150 Aerobat.

“Snap rolls will overstress the wings, and a tailslide will overwhelm the elevators,” added Nik Ahmad Huzlan, who has logged more than 12,000 flight hours on a variety of multi-engined, heavy jets during his 30-plus year career with Malaysia Airlines.

A departure from controlled flight happens when an aircraft exceeds its operating envelope and begins uncommanded movements in any axis. If the aircraft entered into a spin for example, the G-loads exerted on the aircraft could be considerable. If it’s really severe, it could even incapacitate the crew.

Spins are generally recoverable, if you have enough altitude and can implement recovery procedures in time. But if you exceed the loads that the aircraft was designed for, it’s game over.

The loss of a wing, for instance, would induce a violent snap-roll, sending the aircraft tumbling across all axes. The centrifugal forces and the G-loads exerted on the airframe would rip the aircraft apart, if they exceeded the aircraft’s design limits.

The Gabriel BK160T has a maximum G limit of +4.4Gs, and can handle up to -2Gs.

“This aircraft, although it looks like a tough military airplane, is actually under the ‘VLA’, or ‘Very Light Aircraft’ category. The Extra (a purpose-built competition aerobatics aircraft) is on another level, made for extreme aerobatics. VLAs are typically rated at +2.5 to -1.5Gs only, so, I’m not sure if it meets the ‘aerobatic’ criteria in the truest sense of the word.”

By comparison, an Extra 330 competition aerobatics aircraft can go up to +10Gs and -10Gs. The entire cockpit ‘tub’ is a latticework of steel frames, capable of withstanding extreme crash loads. It has a maximum roll rate of up to 420 degrees per second.

“VLAs bridge the gap between ultralights and basic light aircraft like the older Piper Tomahawk or Cessna 152, and the more modern Cirrus (Aircraft with its SR Series), and the (Diamond DA20) Katana.

“Performance, in many cases, can be superior to light aircraft, and are more economical, and cheaper to buy and own. Rules governing VLAs are also more ‘loose’.”

Blackshape’s advertising brochure on the Gabriel BK160TR lists it as “the one and only aircraft specifically designed for training purposes in the last 50 years.

It is designed to offer operational flexibility, comfortable crew accommodation and outstanding visibility both for cadet and instructor. It is equipped with a modern ‘glass cockpit’ environment with dual controls and capable of top performance and flight qualities.

The wings’ aerodynamic design provides excellent behaviour at top speed and low stall/terminal speed, resulting in outstanding safety features and flight characteristics, as well as robust structural and systems installation design”.

The BK160TR has a max level speed of 160 knots and a range of 400 nautical miles.

“That’s up there with most modern, light, general aviation aircraft. These types are meant for ‘recreational’ flying… for getting you from point A to point B where you can enjoy your Sunday brunch and fly back home. They are not rated for extreme G loads,” Nik Ahmad Huzlan added.

Another expert said that a crucial part of the accident investigation would be in the reconstruction of the aircraft.

The lead agency in this case is the Aircraft Accident Investigation Board (AAIB).

“If the wreckage is relatively intact, investigators will then be able to pinpoint the likely source of the failure. It could be a number of reasons – from metal fatigue, improper maintenance procedures, to component failure. They will also look for tell-tale cracks in the fuselage or wings, the empennage (the vertical and horizontal stabs), unusual scorching or burn marks and so on.

“As per the usual practice, they will also scrutinise the aircraft’s maintenance logs to see if there were any irregularities or discrepancies in the aircraft’s maintenance.”

In a statement released on Feb 16, the Malaysian Ministry of Transport said that the aircraft that was lost in the mishap belonged to Blackshape S.p.A, an Italian aircraft manufacturer. Sky Media Ltd of Hong Kong is the authorised distributor of the type in Southeast Asia.

The statement added that Sky Media Ltd had appointed Aviation Safety Technology Pte Ltd (AST), a Singapore company, to market the Gabriel BK160TR. AST had hired Yee to operate, demonstrate, and promote the aircraft to potential customers in Malaysia.

CAAM said that at the time of the accident, the aircraft had a valid airworthiness certificate, issued by the European Union Aviation Safety Agency (EASA).

However, on Feb 16, Blackshape issued a statement saying that the aircraft had been issued with a grounding order. In response, CAAM said it received no such notification from Blackshape.

CAAM, in an earlier statement said that in line with Annex 13 ICAO, a preliminary accident investigation report will be released 30 days from the date of the incident, with the full accident report released at least 12 months from the date of the tragedy.

The AAIB did not respond to Twentytwo13’s request for comments.

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