On Sunday 13 April 2003 the Sea King embarked in HMAS Kanimbla, callsign Shark 07, suffered a catastrophic failure of the No 1 Input coupling while conducting a recce of the AL Faw Peninsular. The aircraft was successfully recovered by the good work by both pilots LCDR Moggach and LEUT Kimlin. The full detail of this incident is detailed in a Touchdown Magazine Edition issue 2 August 2003 and is titled A quiet Sunday afternoon over IRAQ – see the sidebar for an excerpt.
After harrowing events flight 07 made a single engine running landing to a car park in the port facility of Khar Al Zubair in Iraq, which, for the less travelled, is located approximately half way between Umm Qasr and Basra. At the time it was a Forward Operating Base held by the British Marines and elements of the Coalition Forces, including element of the Royal Navy, US Forces and Royal Australian Navy personnel from Clearance Diving Team 3.
The subsequent repair in field was extremely challenging with the aircraft remaining ashore for 16 days. It required a significant maintenance effort by flight personnel, but also outstanding assistance by the Seahawk Flight embarked in HMAS Darwin; Royal Navy’s 845 (Sea King) Squadron, Clearance Diving Team 3 and Logistics support staff in theatre. Finally, the support provided in Australia from 817 SQN, NASPO and the logistics support provide to transport approximately three air transportable pallets to the MEAO was a tremendous feat by all those involved.
I first became aware of the incident at about 1130 that morning when I was piped to contact OPS room, where I was briefed by the Principal Warfare Officer (PWO) that the Shark 07 had made a PAN call having suffered an ECU shutdown while over the AL Faw Peninsular. The OPS staff were extremely busy, as in addition to the PAN situation they were also busy coordinating Force Protection as Kanimbla was in the upper most region of the NAG.
At that stage we did not know where the aircraft was, as information was trickling in via real-time chat, but we eventually received information from HMAS Darwin and HMS Marlborough that the aircraft had landed safely – but no indication where! We had been given what looked like a map grid reference, but I was completely unaware of the location of coalition forces ashore, due to Operational Security (OPSEC).
Shark 07 in Az Zubayr dockyard. The single-engine landing had been performed on the roadway behind the aircraft. Here, it is positioned ready for its first test flight with two engines and a Main Rotor Gearbox replaced. Astonishingly, it only required two test flights before it was fully serviceable: the first covered 99% of the schedule and the second only to adjust the rotor rpm in autorotation – a truly great effort for a small team working in the field. (Anthony Bathe).
Having at last fixed the position of Shark 07, the next stage was to organise transport to the location. We had two other RAN ships operating in our area: Anzac and Darwin, both of which had embarked Seahawk flights so they were a possible option. Discussion with the OPS staff revealed that Anzac was on a port visit, however, and Darwin’s Seahawk had been tasked with logistics duties and was not due to return later on in the evening from Bahrain. As no further viable options were available, our maintenance personnel had no choice but to play the waiting game.
The next step was to come up with a plan based on the limited information available, and we went through a number of possible scenarios with the POATA “Bluey” Gannon and LSATA Frank Green. These were an Engine Change Unit (ECU) failure, which suggested the problem may have been caused by a fuel computer, over speed trip governor, FOD or fuel system.
The next important stage was to brief command on possible situations. Based on the limited information we had I suggested that the ECU may require changing which would take up to two days as we had spare parts onboard carry out this type of rectification.
The other possible scenario was the freewheel unit. Repairs in this case would be a major task as it would require a Main rotor gearbox change, which would take in the order of 1-2 weeks on receipt of stores. Command asked how long it would take to get a gearbox and all the required associated support equipment in theatre. From my experience with other Flights operating in this area, I stated it could take a week or two.
After the command briefing, I continued to chase up if an aircraft had become available for transportation of the maintenance personnel ashore, but there was none.
At approximately 1500 I received an update from the Flight Commander detailing the incident and that they had received support from 845 SQN (Royal Navy) and CDT 3. One of the 845 SQN maintenance Chiefs had examined the aircraft and suspected that the freewheel unit was U/S. He also advised that the crew and passengers were to be flown back to Kanimbla later that evening in a Sea King from 845SQN.
When the RN aircraft landed on Kanimbla the flight maintenance personnel were keen to find out what had happened, and the gravity of the event immediately became clear by the demeanour of the crew.
By Flight Commander
We were conducting the recce for the Australian Clearance Diving Team 3 who were conducting explosive ordinance disposal in the Al Faw area. The flight profile involved a number of low level passes within 1 nautical mile of the Northern shore of the Al Faw peninsula. This was being conducted at 50-70 knots and between 100-200 feet. The helicopter was transitioned into a low (40 feet), slow (20 knots ground speed) pass along any suspect ordinance locations so that the embarked divers could assess the site. We were about 1.5 hours into the sortie and had made significant progress down the peninsula when I saw a large pile of mortar rounds lying on the ground near our flight path. I rolled the Sea King into a 30° angle of bank turn to the left and started to descend aiming to position the helicopter so that the divers could identify the type of mortar round.
The helicopter was about 210° through the 360° turn when things started to go pear-shaped. At about a height of 40 feet and 30 knots airspeed, I heard an annoying whirring sound from above my head.
In the time I had to think, “what the hell is that?” number 1 engine rapidly shut itself down leaving us in a rather unenviable position.
Landing is normally the option that would be taken in these circumstances however it all depends on the nature of the surface you intend landing on – in this case the surface was a soft sandy, muddy texture covered with berms and levees making the required running landing impossible. I was too low to effectively slow the aircraft into a zero-zero landing. The other thing that I vividly remember was that our likely landing point would have been in the exact location of the mortar rounds. The landing would have certainly been spectacular! That left me with only 1 option – to fly away.
The advanced transition technique, which I normally have trouble remembering for the annual check ride, suddenly became crystal clear in my head. I knew what the loud bang was as soon as I heard it.
The sound of the failure followed by the unmistakable sound of the engine winding down did not require a 2nd opinion. I made the ‘war cry’ of “Torque Split, Call Nr” to which the P2 responded with the numbers I needed.
“96, 93, 91, 91”, he called as the rotor speed fell well below the normal 102.8%. I don’t recall how much collective I had pulled in but it was enough to get the remaining engine topped out while the Nr drooped to 91%. The P2 recalls seeing the number 2 torque up around 130%. That engine had been a dog during this deployment but was now working its heart out. Through all this, 91% Nr is the minimum figure for safe flight and is the number that stuck in my head.
Decision time – will she keep flying or are we still going down? With my eyes on the horizon and the Nr stabilising at 91%, we managed to level the aircraft. The P2 remembers the airspeed wavering around the 25 knot mark, barely enough to continue. In this scenario there are 3 figures that all Sea King pilots will have had thumped into their heads during their training – 40 knots, 100% Nr, 65 knots.
We had leveled the aircraft at about 10 feet above the ground and were slowly flying over the many levees and berms that line the peninsular foreshore. I gently trimmed the aircraft forward and hoped that we didn’t descend too much.We were still about 45° out of the wind but a turn in this situation was not viable. The airspeed very slowly increased and finally hit the magic 40 knot figure – things were finally looking up! Next target is 100% Nr. The only way to increase the Nr in such a situation is to lower the drag on the blades, and the only way to do that is to lower the collective. I can guarantee that this is not a natural thing to do when you are flying just 10 feet off the mud but it does work. There is the added bonus that a faster rotor speed brings and that is greater lift. The end result is that I lowered the lever and climbed about 20 feet. So far, So good. Next target 65 knots.
This is the easiest of the 3 targets to achieve but still requires a little finesse. I gently eased the cyclic forward and let the airspeed creep up to 65 knots, trading the newly achieved height for speed. At 65 knots and 100% Nr the aircraft was finally in safe flight and we could commence breathing again.
We subsequently worked through the check list actions and even attempted a restart on the number 1 engine. The start was successful but the Nf over ran the Nr indicating a severe disconnect between the engine and gearbox. We secured the engine and made a decision to land at the port facility at Az Zubayr, just 18nm up the river. Our ship was over 30nm away and as tempting as it was to head home to mother, it just wasn’t a viable option for a single engine landing. We knew that there was a Royal Navy forward operating base at Az Zubayr and that they had a Sea King Squadron in residence. was also a large concrete area that was suitable for the requisite running landing.
We went through the checks and eventually conducted a safe landing.
The Aircrewman, Leading Seaman Jeff Weber, spoke to me and said they were close to “spudding in”. The Observer LEUT Bradley also stated they were close to “pancaking into the AL Faw peninsula”.
The Petty officers and I were then briefed by the Flight Commander, LCDR Moggach, who was the flying pilot at the time. He explained in vivid detail what had happened: that the No 1 engine had shut down in flight during a low-level pass near a stock pile of unexploded ordnance, which was suspected of being from the IRAN/IRAQ war. The crew were able to effect a recovery and fly approximately 30 miles to the port facility where a single-engine running landing was carried out. The RN maintenance crew preliminary assessment was the free wheel unit had failed. This was able to be confirmed as the number 1 ECU could be rotated by hand in both directions indicating the ECU was no longer mechanically connected to the main rotor gearbox (MRGB).
A small maintenance team headed by PO Scott Wake were then immediately sent on the return flight of the RN Sea King, to conduct AFI inspections and determine the feasibility of recovery of the aircraft. I later found out that the crew should have never gone ashore without being correctly force prepared which included escape and interrogation briefs.
The planning then started in detail and the myriad of reports, signals and emails that had to be sent. I also called the Squadron by voice to advise them of the incident, but due to operational security was unable to disclose the actual position of the aircraft.
The maintenance crew returned the next day and briefed the flight on the feasibility of conducting the recovery of 07. The good news was that 845 SQN were eager to assist in whatever way they could and had even requested a number of items of ground support equipment from HMS Ocean.
My preliminary diagnosis was that the MRGB required replacement based on the initial assessment by RN personnel, backed up by the assessment by the Flight’s maintenance personnel. NASPO agreed with my decision and advised they were pulling out all stops to supply the required spares equipment necessary to successfully replace the MRGB and the ECU.
For the next day or so we waited until confirmation of the arrival of stores but also had to gain higher approval for the maintenance personnel to proceed onto Iraq without the appropriate force preparation training.
On the 16 April, three days after the incident, the advance party of Flight maintenance personnel proceeded ashore in an RN aircraft. There were two flights scheduled to depart that day – the first for the maintenance personnel, and the second flight to collect CDT3 after a few days of luxury onboard Kanimbla. The Met brief advised there was a strong chance of a Shamal or dust storm later that afternoon, however, so the second flight was cancelled. The first RN Sea King was therefore loaded up to I would consider maximum capacity with maintenance personnel and CDT 3, together with some of our equipment. I recall the aircraft was heaving to get off the deck and gain forward momentum and blade coning was in excess of anything I had seen or felt before. I also remember hearing over the intercom that the pilots had observed a significant MRGB over-torque while departing Kanimbla’s deck.
The flight ashore was uneventful for the first 30 minutes, but the expected Shamal arrived early and the aircraft had to operate in a 40/40 configuration. I did not know what the crew were talking about initially however the aircraft slowed to 40 knots and reduced height to 40 feet due to the limited visibility in the dust storm. The crew then weaved the aircraft using the waterway as a major reference to navigate to our destination. The bonus was we got to see vessels and equipment that were destroyed from the First Gulf War but I recall we also had to dodge structures such as houses, power poles and wires. The flight took ages and was the most intense flying I had ever experienced. The aircraft landed at the facility with few personnel feeling a bit worse for wear with airsickness, including myself.
The storm then passed and we were greeted by a less than friendly pack of rabid looking dogs who were eying off the fresh sandwiches kindly supplied from Kanimbla. The team commenced removing the blades and planned to then move the aircraft to a more suitable location which, after a quick recce,was determined to be on a section of the wharf. Prior to commencing the move it was decided to undertake a survey of the route to ensure that the road which had railway tracks weaving throughout had sufficient load carry capacity and width to allow a Sea King to be moved to the new area.
Once the planned route was established we borrowed a short wheel base Land Rover from 845SQN and a towing arm to move the aircraft from the car park to the wharf where the aircraft remained for approximately the next two weeks.
Above. Shark 07 with engines and gearbox removed at the port facility at Az Zubayr, Iraq, following an input coupling failure in flight. The repair was carried out over a period of some two weeks in extreme conditions. (Defence Images).
The next day the advance party undertook maintenance in preparation for a gearbox change, removal of both engines and the replacement of No 2 engine in anticipation of the serviceable gearbox arriving from Australia. NASPO had requested an inspection of the input coupling be carried out as this was the main suspect of the cause. This inspection did indeed reveal that the No 1 input coupling had failed, as it showed heat stress and when rotated was found not to internally connect as per a normal coupling. The coupling was packaged and sent immediately to Australia, and proved crucial in the investigation process.
The only oversight from this was that during the removal of the Input coupling that the MRGB housing was not inspected to ascertain if there had been any secondary damage.
The next day the remaining maintenance crew members were shuttled ashore using the Seahawk from Darwin flight, which also load lifted the tool kits and test equipment. I recall the Flight Commander (LCDR Frost) in the back of the aircraft monitoring the load on the FLIR camera, remarking on the frustration of having to do an underslung load as the S70B-2 was limited to 80 Knots in that configuration.
The maintenance personnel meet up with the advance party who had made significant progress, and we then received a brief from CDT3 and shown our place to rest (a tent) for the next few weeks. We were also advised on the security aspects, alarms and muster points as there was still a threat of chemical weapons in theatre. Prior to boarding any flights, we were also issued with a weapon and spare magazines, Kevlar body armour and helmet. After a few days the NBCD threat became non-existent but we were still required to carry around the helmet and armour for a few more days before this was relaxed and only weapons were required.
I recall one of the lads was quite anxious about the fact he had to carry a weapon – he didn’t say much but I presumed he had minimal exposure to it at recruit school and the odd guard. I explained that he shouldn’t worry as there was a large contingent of British Marines who love a fight and if he or I had to put a round up the spout we would be in a world of hurt.
The accommodation we had was a standard issue green tent kindly loaned to us by the CDT3 We each had a stretcher and all our kit placed under the stretcher, and after a day’s work in the heat we all slept like babies. On one particular night we were treated to another Shamal which whipped up while we slept and the tent felt like it was about to be blown away. LEUT Kimlin woke me expressing his concern but I told him it would be fine and went back to sleep.
While ashore we were utilising the supplies that the CDT 3 had as in MRE and the Australian Ration packs, we also got the ship to supply BBQ packs consisting of meat bread sauces and onions which we kindly supplied to the 845SQN. This was the least we could do given all the help they had provided with the use of GSE, including a power cart during the early stages.
We also organised the same BBQ pack for the CDT 3 as they had a freezer and the troops were thankful for our generosity. Unfortunately, the WO of the team was less than happy as we had not received permission from him. However, we still managed to have a few BBQs as we were getting bored of the same rat packs. The only drawback with the BBQs was that the local dogs smelt the BBQ meat they would hang around hoping for a morsel. One evening we forgot to dispose of any rubbish and later on that night there was a massive dog fight after the food left in the bag. We were sternly warned by the WO of CDT3 not to do that again as a member of the coalition forces could have been attacked.
We even swapped our ration packs for the RN ones which had baked beans and exquisite desserts such as treacle tarts. It was a win/win situation as the RN were bored with the same meals.
Good Friday occurred while we were ashore we were luckily enough to get a supply of Easter eggs from our family and friends in Australia.
The maintenance continued at a steady pace. We started work early in the day while it was cooler, although the location we had placed the aircraft gave us natural air conditioning off the river and relief from the blazing sun with adequate shelter.
Late on the 21 April we finally received the stores from Australia which I recall were in three air-transportable pallets. These had been off-loaded in Bahrain and brought by road to the final destination. Maintenance then continued at a good pace as personnel were keen to get back to the ship due to the conditions .
During the removal and installation of the gearbox CDT 3 commandeered a crane from the port facility, and this came in handy as it was also used a transportation around the port. On the 23 April the flight hosted a BBQ with the Junglies which included a game of cricket. The only drawback was we did not have a ball so in lieu we used a toilet roll wrapped in masking tape. The Aussies won the match and the BBQ was well received by the RN.
The good progress of the maintenance was placed on hold waiting for an urgent delivery of a new pair of input couplings from Australia. On the day prior to ANZAC Day the majority of the crew then returned back to Kanimbla for some well-deserved R&R and to partake in the services planned onboard with CDF and the Minister of Defence. There were limited spots available on the flight back so myself and two others remained behind to look after the aircraft and continue with maintenance.
On ANZAC day the remainder of the Flight and I attended the dawn service host by CDT 3 which had a number of attendees from the various units station in the Port. On completion of the service there was a BBQ breakfast then in the afternoon a game of touch football – CDT3 plus the Birdies versus the officers of the Royal Marines. This was a fierce competitive fixture with the CDT 3 winning in the end.
The maintenance team planned to depart the ship on 26 April, but this was delayed until the following day and they were treated to an eight-hour trip in an LCM8. It was made worse by the bitter cold during the night, and in an attempt to stay warm a number of personnel donned NBCD suits.
By 28 April the majority of the maintenance was completed and the aircraft was moved back to the car park to install the blades and carry out all the required preparations post such an intensive maintenance evolution.
Late on the 29 April after a morning of ground runs and one maintenance test flight Shark 07 returned to Kanimbla FMC. The following day Shark 07 returned to pick up the flight stores and equipment plus return the support equipment to 845 SQN who had now moved north and were now operating out of Basra Airport.
We did have our setbacks – for example, a lost tool. I suspect it had been gathered up in the multitude of rubbish we generated from having to eat “Rat packs”, and ended up in the bottom of the burn bin where it was eventually found. There was also a type of grease we didn’t bring with us from the ship however we did manage to borrow a tube off the Junglies before they departed to Basra.
Of significance the previous year (2002) while 07 was at NAS Nowra there were a number of unscheduled major maintenance activities, which I recall included two main rotor gearbox (MRGB) changes within a short period of time. The Flight were unaware they were practising for the future MRGB change in IRAQ in April the following year!
Of significant note on return to Australia and back at 817 SQN LEUT Kimlin, who had been the co-pilot on the uncommanded shutdown of Shark 07, heard a strange noice whilst starting another aircraft. The aircraft was shut down and returned to maintenance, and after a great deal of debate he surmised that the input coupling was at fault as the noise was remarkably similar to the noise he had heard prior the failure of Shark 07.
Both ECUs were removed and the input couplings were inspected, with the port coupling showing evidence of overheating. The front frame was then inspected and also showed signs of overheating. Maintenance personnel then noticed particles on the oil jet above the coupling, which appeared to be blocked. This incident led to additional monitoring of all input couplings to ensure that no further failures occurred.
About the author:
Anthony Bathe was the FSMS Chief Petty Officer Aviation Technician Avionics, or the head of the aviation maintenance personnel of HMAS Kanimbla Flight at the time of the above incident. He joined the RAN in Jan 1982 as an apprentice and discharged in July 2006. The majority of his 24 years of service was on the Sea King, including to a number of Ships flights and detachments. After a six and a half year stint as a public servant working at NASPO supporting the Bravo, he re-joined the RAN in Jan 2013 and is currently working on the Romeo or MH60-R at both 725 SQN & 816 SQN.