1. Introduction
	2. The Previous Flights
	3. The Accident
	4. Alert Procedure
	5. Assistance
	6. Summary and Conclusions

2. The Previous Flights
2.1. Introduction. The Hercules in question belonged to the Belgian Air Force, and was put into operation on 15 July 1996 for the Royal Netherlands Air Force. The aircraft had undertaken a number of flights that day, prior to the fatal moment.

2.2 The flights.
The CH-06 had left its home base of Melsbroek, near Brussels, to call first of all at Eindhoven Air Base. At Eindhoven a quantity of freight was loaded into the aircraft on pallets, intended for transportation to Villafranca in Italy. Seven passengers also boarded the aircraft, four of whom had Villafranca as their final destination and three Rimini, also in Italy. Once the passengers and freight were on board the Hercules departed for Villafranca, where it landed at 13.33 hrs. There were no irregularities during this flight.

2.3. In Villafranca the passengers left the aircraft and the freight that had been loaded in Eindhoven was unloaded.
The aircraft was also fuelled. The crew of the CH-06 had lunch at the Air Base, after which 37 passengers boarded the aircraft. The passengers were made up of 34 members of the Royal Netherlands Army's Brass Band, one member of the Royal Military Band, one civilian musician on contract and an official from the Defence Movement and Transport organisation. The musicians had given several performances in Italy and were to be taken back to Eindhoven in the Hercules. Furthermore, three of the original passengers from Eindhoven reboarded the aircraft.

2.4. The aircraft did not fly directly from Villafranca to Eindhoven, but flew via Rimini, where the three remaining passengers who had flown from Eindhoven were to disembark. The aircraft left Villafranca at 15.04 hrs, landing at Rimini at 15.31 hours. This flight also took place without irregularities.

2.5. After the landing at Rimini, the aircraft taxied to an apron at the top of the runway, where the aforementioned three passengers disembarked through the loading flap. The engines of the aircraft were not turned off during this procedure. Owing to the air traffic situation, a further 20-minute wait was necessary before air traffic control was able to grant take-off clearance to the crew. The CH-06 finally took off at 15.55 hrs with Eindhoven as its destination. At that time the crew, consisting of four people, and the 37 passengers from Villafranca were on board.

2.6. The CH-06 flew directly to the Netherlands from Rimini.
In doing so it passed, among others, the radio beacon in the vicinity of Thorn, near Weert in the Netherlands. At this point the Hercules crew contacted air traffic control at Eindhoven Air Base by radio. Eindhoven ATC then granted clearance for a visual approach, by means of a right turn. In this instance radio communication was conducted by the pilot in command of the aircraft. In view of the fact that in general radio communication is conducted by the pilot who is not operating the aircraft, it can thus be deduced that at this particular point in the flight it is highly likely that the aircraft was being flown by the second pilot. The second pilot was, incidentally, fully qualified to do so. After obtaining clearance, the descent was continued. By making a right turn the aircraft was lined up with runway 04, which runs in a north-easterly direction. As a consequence, the aircraft was directly aligned with the runway at a distance of some 1.5 kilometres. It subsequently flew in a north-easterly direction, in other words in the direction of the runway. This was both a correct and customary approach pattern.

2.7. Shortly before the actual landing was to have taken place, the crew of the Hercules initiated what is known as a missed approach procedure. This involved the crew fully opening the throttle with a view to circling in order to approach the runway again. This procedure was not in accordance with the announcements made during the aforementioned radio communication that took place when the aircraft was in the vicinity of Thorn - a 'full-stop landing' had been announced at that juncture. The decision to conduct a missed approach procedure can therefore only be explained from the assumption that the pilots must have believed that it was impossible at that moment to undertake a safe landing. Investigations have shown that a large number of birds, which the aircraft incidentally also struck, were located at the top of the runway. It must be assumed that the crew observed the birds at the last moment, and then made the decision to undertake a missed approach procedure. Air Traffic Control was not notified of this decision, owing presumably to lack of time.

3. The Accident
3.1. Introduction.
After the accident, investigations were conducted into, amongst others, the technical condition of the aircraft, a brief summary of which is given below. The immediate cause of the accident was the fact that the aircraft struck a group of birds, as a result of which the aircraft found itself in an untenable situation.

3.2. Technical condition of the aircraft.
It has been established that the aircraft had undergone all prescribed periodic inspections. No terms for periodic inspections had been exceeded.

3.3. The technical investigation has shown that the aircraft was in good technical condition. On 15 July 1996 the CH-06 was therefore fully airworthy.

3.4. In summary, it can be said that the aircraft was in good technical condition and that nothing has been determined in this respect that could have influenced the accident in any way.

3.5. Birds.
Shortly before the landing of the CH-06 a flock of birds was observed from the control tower. The birds were on and around the runway at the level of the tower. They were then driven away by several bird-scaring rounds being fired from the tower. The flock of birds subsequently moved northwards and was not observed again. At 18.00 hrs the bird scarer, an official specially tasked with observing and if necessary driving away birds, was present at the control tower. Before the landing of the Hercules the bird scarer, as did the air traffic controller, used binoculars to check the top of runway 04 for the presence of birds. No birds were observed.

3.6. Although no birds were observed from the control tower, regrettably a large number of birds were to be found around the start of runway 04. Investigations have shown that there were between 500 and 600 starlings and lapwings, most of which were presumably in the grass around the runway. The grass had been mown several days before, and the mown grass still lay on the ground. If the birds were in the mown grass, it is understandable that they were not seen.

3.7. The flock of birds took flight immediately before the CH-06 was to land on runway 04. It can be assumed that they did so as they were startled by the approaching aircraft. The CH-06, whose crew decided to implement a missed approach procedure when seeing the birds, struck the flying birds.

3.8. The accident. During the missed approach procedure the flock of birds, seen from the flight direction of the aircraft, flew in front of the aircraft from right to left, in a cluster. As a result, the aircraft was hit by a large number of birds on the cockpit, and - mainly - on the left wing.

3.9. As a consequence of the bird strike, a number of birds got into the engines, as a result of which engine 1 (the outermost engine on the left wing) and engine 2 (the innermost engine on the left wing) lost power. The technical investigation does not give conclusive evidence as to whether there was also a loss of power in engine 3 (the innermost engine on the right wing) as a direct result of the bird strike. After the bird strike the crew set the propeller of engine 3 to minimum drag ('feathering'). As a result, the engine no longer gave any output. The investigations have shown that this took place before the aircraft came into contact with the ground. The result of the foregoing was the fact that engines 1, 2 and 3 had lost their capacity. However, engine 4 (the outermost engine on the right wing) was still functioning normally, and as a result of the missed approach procedure initiated by the aircraft its output was almost at the same level required for take-off.

3.10. As a result of the situation described above, the aircraft rotated to the left, and quickly lost altitude. Approximately nine seconds after the bird strike the left wing tip of the aircraft hit the ground. By this time the aircraft had turned approximately 70 degrees to the left from the original flight direction, and had banked at an angle of approximately 35 degrees to the left about its longitudinal axis. The left wing tip broke away from the aircraft after coming into contact with the ground. The exterior fuel tank on the left side of the aircraft, located under the wing, was also damaged, causing fuel to run from the tank, as a result of which the ground caught fire. Immediately afterwards the propeller of engine 1 hit the ground and broke away. Subsequently, the propeller of engine 2 came into contact with a hard object, possibly debris from the broken wing tip. Consequently, this propeller also broke away.

3.11. The aircraft then turned further to the left, touching the ground several times at short intervals. Shortly afterwards it finally landed on the ground, and continued to slide along the ground. In doing so the nose of the aircraft ultimately lay at an angle of 90 degrees to the flight direction of the aircraft, causing it to slide further sideways, during which the aircraft banked to the right about its longitudinal axis. This caused the right-hand undercarriage to break away. Subsequently the propeller of engine 4 hit the ground and also broke away. Then the right wing tip touched the ground, causing the fuel tanks there to tear open, upon which fire broke out across the right wing. The right-hand rear elevator then hit the ground. The aircraft continued to slide for another few dozen metres, finally coming to a start, in flames, at 18.03 hrs. It finally tilted to the right, with engine 4 resting on the ground.

3.12. The aeronautical investigation has shown that wherever possible the crew carried out the procedures prescribed for such a situation. They then moved to the hold of the aircraft.

3.13. Almost immediately after the aircraft had come to a standstill, it caught fire at the level of both wings, with the fire on the right-hand wing being the most severe. Shortly afterwards, an oxygen-fed fire broke out at the level of the bulkhead between the cockpit and the hold. This fire was fed by oxygen from the aircraft's oxygen system damaged by the impact. The fire was extremely severe, and blocked the access to the cockpit for both passengers and crew, who at that time were all in the hold. The oxygen fire also caused a metal fire, which made a large hole in the fuselage, just in front of the right wing. Owing to the severe fire both inside and outside the aircraft, it was impossible to leave the aircraft by the right-hand emergency exit.

4. Alert Procedure
4.1. Introduction.
The air traffic control in the tower alerted the air base fire brigade and ambulance. Soon afterwards, the air base Emergency Centre alerted the civil ambulance and fire service.

4.2. Internal alert procedure. Immediately after the initiation of the missed approach procedure, and during the fatal descending left turn, the air traffic controller on duty anticipated an accident. At 18.03 hrs he activated what is known as the 'crash bell', and using the air base public address system announced that the Hercules had crash-landed, giving the location of the aircraft. At the same time, the assistant air traffic controller contacted the Emergency Centre of the air base fire service, and reported the situation. The fire service turned out immediately. Shortly afterwards, at around 18.06 hrs, the ambulance of the Military Medical Corps also turned out. The alerting of the air base services and the responses to the alert were thus satisfactory.

4.3. External alert procedure.
When reporting an air crash to external organisations, the switchboard operator of the air base fire service Emergency Centre is instructed to report the applicable scenario. Scenario 1 applies in cases where no more than two people are involved in the accident, scenario 2 for between three and ten people, and scenario 3 applies when more than ten people are involved. The procedures to be followed and the number of organisations to be notified depend upon which scenario is reported. The procedures to be followed are laid down in checklists for the various officials involved.

4.4. The air traffic controller on duty had been informed by a private source that the Royal Netherlands Army's Brass Band was on board the aircraft. He was therefore aware that there were at least 25 people on board.

4.5. At approximately 18.04 hrs the air traffic controller telephoned the air base fire service Emergency Centre (EC), instructing them to dial 06-11 (national emergency services). The statements from the air traffic controller and the switchboard operator in question differ with regard to the further content of this conversation; the air traffic controller states that he added that both extra fire engines and ambulances were necessary, as there were at least 25 people on board the aircraft. The switchboard operator only remembers receiving instructions to arrange for extra ambulances. At 18.06 hrs the switchboard operator dialled 06-11 and was put through to the Central Ambulance Post (CAP). The switchboard operator was not aware that 06-11 is used to pass on alert messages to the emergency services. He expected that to report to 06-11 the fact that a Hercules had crashed was enlist the help of the emergency services. The use of 06-11 was unnecessary, and in this case served to create delay and confusion.

4.6. At approximately 18.04 hrs the duty commander of the air base fire service, known as the On-Scene Commander (OSC), asked air traffic control to inform him of the number of people on board. Because the air traffic control tower had no precise information in that respect, according to the air traffic controller the response was that the precise number was not known. According to the OSC, the response was 'nothing known' or something to that effect. Because the OSC was aware that the crew of a Hercules consists of at least four people, according to his own statement he then informed the EC by portable radio-telephone that scenario 2 was in force. The switchboard operator states that he did not hear this. However, in view of the hectic situation at that time he will not preclude that the message was indeed passed on.

4.7. At approximately 18.07 hrs the EC switchboard operator was assisted by a fireman. Together they tried over the next few minutes to notify a number of officials of the situation by telephone. The officials included the Head of the Air Base Fire Service, personnel from the Air Force Security Service, the Commander and Deputy Commander of the air base, the Head of the Unit Operating Safety Office and the Royal Marechaussee.

4.8. At approximately 18.12 hrs the Regional Emergency Centre (REC) of Eindhoven Fire Service, which had been notified by the police at 18.09, telephoned air traffic control and asked whether assistance was required. Air traffic control relayed the question by mobile radio telephone to the fire service at the scene. Someone from the air base fire service heard the question on the mobile radio telephone and responded 'negative'. Air traffic control then thanked the REC for offering to help.

4.9. At approximately 18.12 hrs the EC switchboard operator and the fireman then assisting him decided themselves to act in accordance with scenario 2 of the disaster plan, on the basis of the fact that a Hercules carries a minimum of four people. At 18.15 hrs the EC contacted the REC and reported the accident, without notifying them of a scenario. The first civil fire-fighting vehicles subsequently turned out at 18.16 hrs. Had the REC been notified immediately after the crash, this could have taken place ten minutes earlier.

5. Assistance
5.1. Introduction.
A description of the fire-fighting and rescue by the various fire services is given below, followed by the deployment of medical support capacity.

5.2. Fire services.
Immediately after the air traffic controller gave the alert, the Royal Netherlands Air Force (RNLAF) Fire Service responded to the call at 18.03 hrs. This fire service consisted of one Landrover command vehicle (LARO) carrying the OSC, and two Major Airport Crashtenders (MACs), each carrying three people. The aforementioned conversation between the OSC and air traffic control regarding the number of people in the aircraft took place by mobile radio telephone while the fire service was on its way to the scene. Military aircraft of the same design as the Hercules take off from and land at Eindhoven Air Base on a daily basis. Most of these flights carry passengers. The Hercules is equipped for transporting both freight and passengers; there is often a combination of the two uses. However, the OSC assumed that only the crew was present. All his subsequent actions up until the moment that the first passenger was found, would be based on this assumption.

5.3. At approximately 18.05 hrs the fire-fighting vehicles arrived at the ditch at the level of the crashed aircraft. The OSC drove his LARO through the grass to find the appropriate access route to the scene of the accident, which was surrounded by a ditch, and to point this out to the MACs following behind him.

5.4. At approximately 18.07 the MACs assembled for attack, at which time the aircraft was on fire across the width of the fuselage. Furthermore, heavy smoke had developed and kerosene was burning on the right hand side of the aircraft. There was a large hole on the right of the fuselage, behind the cockpit. In accordance with procedures, the extinguishing operation was concentrated on extinguishing the fuselage fire, and preventing it from restarting.

5.5. At approximately 18.09 hrs the fuselage fire had been extinguished, and the fire fighters had contained the remaining fire. In fire-fighting terminology this is known as a 90% knockdown situation. Once a 90% knockdown situation has been achieved, any survivors can leave the aircraft independently, and rescue procedures can be started.

5.6. The OSC subsequently reconnoitred the area around the aircraft. In doing so he observed a metal fire in the left engine. However, this did not constitute an immediate threat to the fuselage. The OSC therefore decided to continue to focus the extinguishing operation on the firght wing and engine. At around 18.10 hrs the water tank of one of the MACs was empty, and that of the other MAC was only one-quarter full. Consequently, the OSC decided to exchange the empty MAC for a full one, which was still standing at the air base fire station. He therefore sent one of the firemen to exchange the MAC. The fireman returned with a full MAC after approximately six minutes, which was subsequently positioned near the right wing. After using a combination of foam, powder and water, the fire in the right wing and engine was fully under control at approximately 18.19 hrs.

5.7 At 18.25 the first vehicles from Eindhoven Fire Service arrived at the ditch and approximately a minute later they were at the crash scene. The OSC subsequently contacted the fire commander of the first water tender, who states that he was told at this moment that there were probably four casualties in the cockpit. At the request of the OSC the civil fire service first of all siphoned water to the MACs, after which the extinguishing of the metal fire in the left engine started at approximately 18.38 hrs. At around 18.33 hours the decision was made to enter the aircraft through the hole in the fuselage, to subsequently extinguish the small fires inside the aircraft using high-pressure (water) jets. At approximately 18.37 hrs a fire-fighting team entered the aircraft for the first time. Shortly afterwards the first casualty was discovered in the hold. Another fireman discovered almost simultaneously that there were between 20 and 30 casualties in the hold.

5.8. Rescue procedures. Once the fire was under control at approximately 18.10 hrs the OSC was able to confine himself, as far as fire-fighting was concerned, to ensuring that no further fires broke out on the fuselage. He could then have released personnel to undertake rescue activities. He therefore could have decided at that moment to initiate a rescue procedure. However, he failed to do so. It would later become apparent that it was possible to partially open the left-hand rear door, as the loadmaster had tried to open this door from the inside immediately following the crash. Although he had managed to unbar the door, he had not managed to actually open it. However, the OSC could have opened the door further using the hydraulic spreader that was at his disposal. This did in fact happen at a later stage. As well as rescue through the left-hand rear door, the OSC could have started another rescue procedure through the hold on the right-hand side of the fuselage at 18.19 hrs, once the fire was fully under control. This did not happen either.

5.9. There is no clarity as to why neither a rescue operation using the left-hand rear door was initiated at 18.10 hrs, nor a rescue operation through the hole in the fuselage at 18.19 hrs. However, an important factor in this respect is that the OSC, and the other emergency officials, was acting solely on the basis of the presence of a crew of four people. In their view, the crew would be in the cockpit and, in view of the severe fire at the level of the cockpit, their chances of survival would be non-existent.

5.10. Once the first casualties had been discovered at approximately 18.38 hrs, the situation changed totally. From that moment onwards, it was suddenly clear that the aircraft was also carrying passengers. Shortly afterwards, the message was received at the crash site from the EG that there were apparently around 40 people in the aircraft. This message had been passed on from Melsbroek to the air traffic control personnel in the tower. The first casualties were brought out of the aircraft at 18.41 hrs. It was then decided that another point of entry had to be found on the aircraft, after which it was discovered that it was possible to open the left-hand rear door by 10 to 20 cm. The door was opened further using a spreader. At approximately 18.46 hrs the door was pushed some 60 cm upwards, using the spreader, during which one casualty fell out of the aircraft. Attempts to open the left-hand rear door even further and to open the loading flap failed. All casualties therefore had to be brought from the aircraft by the two openings created thus far. Approximately two-thirds of the casualties were brought out through the left-hand rear door, the remaining casualties through the hole in the right side of the fuselage.

5.11. Medical relief.
At approximately 18.12 hrs the Military Medical Corps ambulance was the first to arrive at the scene. On the basis of the information from the EC and the CAP, another two ambulances from the Municipal Health Service were also on the way. The nurse from the first Municipal Health Service ambulance took on the responsibility of medical coordination.

5.12. The CAP had in the meantime sent another two ambulances to the airfield. The CAP had also contacted various hospitals and warned them of the arrival of one or two casualties with burns. At 18.40 the CAP received a request to send several ambulances urgently, because the aircraft was carrying more people than expected.

5.13. A casualty collection point was set up at the crash scene. The air base medical officer and the nursing personnel began administering medical aid as soon as the first casualties arrived. A water tender was used to provide water in order to cool burns. The situation at that moment was hectic. The number of people requiring medical aid unfortunately proved to be relatively few, as a result of which the hectic situation did not last long.

5.14. Consequences of the time of rescue for medical assistance. The medical investigation has shown that the chances of survival of the passengers and crew would have been greater if the rescue had taken place at an earlier time, as a result of which the casualties would have been brought out of the aircraft sooner. Regrettably, it must therefore be established that if the OSC had started the rescue procedure at 18.10 hrs the number of fatalities would probably have been smaller.

6. Summary and Conclusions
6.1. On 15 July 1996 a C-130 Hercules from the Belgian Air Force left Melsbroek for Eindhoven Air Base. It then flew to Villafranca and Rimini in Italy. The Hercules subsequently returned to Eindhoven. At that moment there were 37 passengers on board, in addition to the four crew members.

6.2. During the landing at Eindhoven the crew of the Hercules observed a large number of birds, upon which they decided to initiate a missed approach procedure. During this missed approach procedure the aircraft struck a large number of birds, as a result of which it veered to the left and quickly lost altitude. The left wing tip of the aircraft subsequently hit the ground, causing it to break away. The aircraft proceeded to slide across the ground, ultimately coming to a standstill, in flames.

6.3. While the aircraft was still following the missed approach procedure, the air traffic controller on duty anticipated an accident. He then immediately activated the 'crash bell', and reported the accident over the public address system. As a consequence, the fire service of the air base responded immediately.

6.4. Air traffic control was aware that the aircraft in question was carrying the members of a Royal Netherlands Army brass band. However, the air base fire service was unaware of the number of people on the aircraft. The air base fire service assumed that only the crew members were present (four people). In view of the nature of the fire in the foremost part of the aircraft, expectations were that the crew members had lost their lives. Hercules aircraft arrive at or depart from the air base on a virtually daily basis. More than half of the Hercules flights involve passengers, in addition to the crew. However, the air base fire service did not take into account the possible presence of passengers. The CAP, through 06-11, received the first notification from the air base at 18.07 hrs. The municipal fire service was not notified of the situation until twelve minutes after the Hercules had crashed. Notification of the civil emergency services was unstructured and slow.

6.5. The fire-fighting was handled well from a tactical point of view. The fire on the aircraft fuselage was extinguished quickly. The rescue of the crew and passengers could have been initiated at least 25 minutes earlier. Had this been the case, the number of casualties could possibly have been fewer.

6.6. The rescue of the 41 passengers and crew and the evacuation to an improvised casualty collection point took place quickly once the casualties had been discovered. Over forty minutes after the discovery, the ten casualties who were still alive were evacuated to the various hospitals.