The wreck of VIP helicopter H-253 photographed immediately after it fell in the Vukovar military barracks, which was refitted contrary to all regulations and in spite of there being no documentation from the Russian manufacturer for that kind of refitting The results of the investigation of the commission that investigated the fall of a Mi-8 VIP helicopter in Vukovar last year have shown without a doubt that the top national leadership, and very often the foreign officials who joined them, were for ten years in grave danger as they were being transported by an aircraft that had no valid manufacturer documentation that would allow for its proper maintenance. Helicopter H-253 was modified from a transport variant to a VIP version following the "do-it-yourself" principle. The Croatian President, Prime Minister and ministers, and top military officials were in fact riding in an "illegal" VIP helicopter modified in Croatia without the permission of the manufacturer.

The command for this impermissible activity was adopted on 29 April 1997 by Assistant to the Minister for Logistics, General Vladimir Zagorec. Helicopter H-253, just like all off the Mi-8 MTV1 type helicopters, were procured in the 1990s, at the height of the war, while Croatia was under embargo. As a result, legally speaking, according to the manufacturer of the helicopter, Croatia is not a country that uses helicopters of the cited type. The only legally procured transport helicopters from the Mi-8 series are the Mi-171Sh helicopters procured last year from the clearing debt, and the Mi-17 helicopter number H-215 used for medical operations. Because helicopter H-253 was procured illegally it lacks the necessary official documentation that would provide for proper aircraft maintenance. A contract cannot be concluded with the manufacturer on the procurement of maintenance documentation, nor can a contract be concluded on the periodical updating of the documentation if you are not a legal user. As a result of all this the Aeronautics Technical Institute was ordered in 1997 to itself draft documentation on the modification of a VIP version during the time that Staff Brigadier Mladen Vragotuk was at the head of the Technical Administration. In September he issued a temporary licence for the use of helicopter H-253 and ordered the Aeronautics Technical Institute to submit for approval by 31 December 1997 the complete documentation for the modification. He subsequently approved the modifications in disregard of all regulations and standards. The purpose of issuing a confirmation of homologation and the consistency of the type with its use and of the drafting of an Operational Manual and Maintenance Program is evident from this. They provide for the maximum strictness of the criteria for use and technical maintenance for an exactly determined aircraft if the operator so requires.

These kinds of ordinances are certainly not adopted by the Aeronautics Technical Institute. It was only last year, after a full fifteen years that the Croatian Air Force has existed, that a department was established at the Ministry of Defence following amendments to the Defence Act that is to work on procuring maintenance documentation, contracts on the periodical updating of this documentation and the like, but it all came too late for those who died in H-253. Everything should be stricter on VIP helicopters. The HMX squadron, i.e. the US VIP/Presidential squadron, can serve as an example in this regard. The term "recurrent discrepancy" exists in the operational manuals and maintenance programs of their aircraft, i.e. a repeating fault/breakdown. If a fault/breakdown is observed on an aircraft three times in a row that aircraft is decommissioned from the fleet without delay. In Croatia the VIP helicopters designated as H-253 and H-254 are treated as common transport helicopters, and the procedures used on VIP helicopters in the USA can only be applied when the two Mi-171Sh VIP helicopters arrive in Croatia next year. In a study on the separation of the Aeronautics Technical Institute that was submitted three years ago to then Minister Berislav Roncevic documentation was also sought for the Mi-8 helicopters, which has to this day not been submitted to the Aeronautics Technical Institute. In spite of all this they continue to behave at the defence ministry as they did ten years ago. These days they rejected a request to procure documentation related to the Pilatus PC-12 aircraft because there are allegedly no funds to do so. The funds would probably be found quickly if a tragedy were to occur on the Pilatus aircraft. Defence Minister Branko Vukelic should react immediately therefore because safety has no alternative, especially when it comes to aircraft.

Assistant Minister for Logistics Vladimir Zagorec issued the command to modify the Mi-8 helicopter into a VIP version From what has been cited it is clear that Minister Vukelic was quite rash and in error in pointing to the Aeronautics Technical Institute as the clear culprit during last week's press conference during the presentation of the results of the investigation into the fall of the helicopter. The claims of the defence minister are also dangerous because of the fact that the report is also the basis of the investigation of the State Attorney's Office and police investigators, so that his statement could be interpreted as prejudicing the outcome of a court ruling, especially if when those kinds of statement are incorrect. The report of the commission that investigated the causes of the fall of helicopter H-253 also require a more detailed analysis.
The fact is that the commission did not carry out its primary function, that of providing unambiguous answers and evidence of what caused the fall of helicopter H-253. Proof of the cause of the fall is not an analysis at the Brodarski Institut (Shipbuilding Institute) on whether foam could hamper or block the flight controls. Of course it can, but under certain conditions and circumstances. The commission did not provide firm evidence that that was what had in fact happened aboard helicopter H-253, using, rather, the phrasing "I can be stated with a high degree of certainty…" What that statement could mean in a judicial process is hard to imagine. If the high degree of certainty in the conclusion is, for example, 80 percent, does that mean that the punishment meted out to the responsible parties will be reduced by 20 percent?

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And if isolation foam, which is alleged to have impeded the movement of the controls, is cited as the cause, then it should have been stated clearly at which point during the flight, which foam and at what location did it impede the use of the controls. None of this was presented to the public last week by the commission. Not only could the foam not be brought into connection with the cause of the helicopter's fall from a single photograph at the presentation, but the entire report abounds in deficiencies and doubts. Some very important things the manufacturer stipulates were glossed over that concern VIP helicopters, as a result of which the responsibility falls again on the defence ministry structures that were responsible for securing all documentation.

The aircraft manufacturer has set the operational time prior to the first overhaul for Mi-8 type VIP helicopters at four years, and not the ten years valid for transport helicopters of the same type. Helicopter H-253 completed its full operational time of ten years to the first overhaul as if it was a common transport helicopter. Furthermore, a VIP helicopter can only be used in its VIP version up to the first overhaul. After that it has to be refitted as a transport version and can no longer be used as a VIP aircraft. That did not happen. Only new spare parts are built into VIP helicopters. In other words, spare parts cannot be remounted, which was also not abided by.

Of course, had the commission come out with this information, many in the commission would have fallen out with the defence ministry and state bodies so that it was better to remain gloss over them. When it comes to the contentious findings of the commission it should be said that it had to be entirely summed up on two to three pages with explanations included for all three possible culprits – human error, machine error and the environmental circumstances. They did not answer the question why they excluded the human, i.e. pilot, factor and the factor of the environmental conditions from considerations on the cause of the accident, concerning which much could be said. Concerning the pilot, what was the state of the crew on that day, did they all pass medical exams prior to the flight, did any of them have a medical ban, had they all been to training in line with the requirements of the assignment, why did the pilot not react for longer than ten seconds to the evident spinning of the helicopter around its vertical axis, how did the crew influence the outcome, was the reaction of the pilot and crew good or poor? When it comes to the environmental conditions, what was the physical state of the atmosphere on the day in question, the air density, temperature, was their a wind blowing, was the helicopter guarded at the takeoff location, did anybody enter it while it was on the ground, how did the environmental conditions affect the outcome?

In the end the commission should have proposed measures to ensure that these kind sof things do not happen again. The fact is that there is another helicopter, H-254, fitted in the same VIP version as the downed H-253. The H-254 remains flight operational since the fall of its twin H-253, and the commission has told the public nothing to this effect. Instead of irrefutable evidence the commission tried to impress journalists with their three-dimensional animation of the fall of the helicopter, a reconstruction flight in Vukovar, thousands of pages of written material, of which at least two thirds is technical documentation, not their own work, and the like. In its press release the commission established with a very high degree of certainty that the accident was caused by the fact that the foam, as an isolation material, hampered the movement of the cyclical steering controls.

Defence Minister Branko Vukelic rushed to his conclusion in publicly declaring the Aeronautics Technical Institute the evident culprit for the accident Foam was found after the accident in the steering controls area, on the inner side of the protective panel in the cabin area and on the floor of the helicopter. A technical analysis has determined that the foam placed on the controls create resistance and impede their movement, and can in some cases block them. It is quite clear from that finding that there was no foam or piece of foam that had become stuck in the controls area, therefore there was no sandwich-effect of compressed foam in any of the openings through which the controls run, which would certainly have turned up in the investigation if it had been there. If nothing was jammed it is an open question how foam with its almost negligible weight or some kind of pressure could have completely blocked the controls, as pilot Robert Garic, according to his statements, was unable to undertake anything. Obstructed flight control, for example, can result form hydraulics failure, but it is a part and parcel of pilot training and there are safe ways for the pilot to land the aircraft in that kind of situation.

That means that Garic should have known how to land the aircraft if flight controls were only impeded, which is what the commission is saying. The fact that is evidently important to the commission, that foam was found on the floor, is entirely irrelevant, because it is likely that parts of the metal plating, carpeting and colour, and wooden parts of the interior were also found on the floor from the force of the impact. The helicopter was twice raised and lowered for transport and that to is a cause of the falling apart of its interior.

The commission's manipulations

At the press conference the commission created the false impression that it had documentation from the Russian manufacturer that forbids the installation of aluminium foil and foam above the fixed flight controls. The paper they were waving around they in fact received from the Aeronautics Technical Institute, and its experts knew very well what was allowed, and was not. Dinko Vodanovic from the commission is manipulating with these documents because the foam above the fixed flight controls did not fall off. That fact is that they were never there.
This case demonstrates why a representative of the Aeronautics Technical Institute was not included in the work of the commission – because their presence would have prevented this kind of manipulation.

An analysis of the animation of the defence ministry's accident – Questions the commission did not answer

A little more than a year has passed from the accident in which three lost their lives to the results of the investigation Between seconds 0 and 2 the helicopter takes off and hovers ay a height of 0.5 to 1 m. All the commands are working, the helicopter is stable. The cyclical stick is operational because the pilot, in order to hover, has to move the cyclical stick to the left and back. Between seconds 2 and 4 the helicopter rises vertically to a higher altitude in order to clear the nearby hangars. Everything is still in order.

Before hovering at this greater altitude, between seconds 5 and 6 the helicopter's nose begins to rotate to the left, which it continues to do until it comes into contact with the ground, and this is, in fact, where the accident begins. On helicopters on which the rotor turns to the right the reactive moment of the main rotor tends to move the helicopter's nose to the left.
The pilot adjusts for this reactive torque by increasing the torque of the tail rotor, depressing the right pedal control. Why does the pilot not react here and land the helicopter? The tendency to move the helicopter's nose to the left increases as the power is increased on the main rotor. That means, more power, more right pedal. While hovering to this greater altitude the pilot (which is visible from the animation) pulled energetically on the thrust and (as it is said in the jargon) was "a little late on the foot". That is why he was not surprised by anything.

Over the next couple of seconds (from 2 to 3) the helicopter rotated almost a quarter circle – and that is when the complications start for the commission. It is evident from the animation that the helicopter moved forward, which means that the cyclical stick had to have been moved forward. That means that here again the problem is not with the impeded movement of the cyclical control, as they wish to say. But what is with the rotation of the helicopter? Why was it not stopped, and could have been? At which second of the takeoff did the cyclical stick become jammed? None of that was explained at the press conference.