Latest news with #APU
Yahoo
7 days ago
- Business
- Yahoo
KC-46 Crews Ordered To Drastically Curtail Use Of Jet's Onboard Auxiliary Power Unit
The U.S. Air Force's fleet of KC-46 Pegasus air refueling tanker fleet is experiencing problems with its auxiliary power unit (APU), a small secondary turbine engine at the back of the plane that primarily provides electricity to run systems prior to the startup of the main engines. It is also used to self-start the aircraft on the ground without the need for cumbersome ground support equipment. The problem has gotten so bad, Air Mobility Command (AMC) recently sent out a memo curtailing the use of the KC-46's APU, The War Zone has learned. The APUs are intended to make the KC-46s less reliant on ground crews and equipment prior to takeoff, but the issue is having the opposite effect, the Air Force told us. 'AMC has seen some premature failures of APUs we're working with the (Original Equipment Manufacturer) OEM to resolve,' an AMC spokesperson confirmed to us Monday afternoon. 'This memo ensures our maintenance team uses ground support equipment whenever possible to reduce APU wear-and-tear, giving us the best availability while we work through repairs.' It isn't clear when the problem was discovered or how long the workaround will be in place. Having to rely on ground systems, including power carts for accessory power and huffers carts for engine start, requires a larger logistical footprint and more personnel on the ground. It's also an inconvenience to the crew. Above all else, it diminishes the aircraft's ability to operate in austere conditions, a key component of the Air Force's Agile Combat Employment (ACE) program. ACE currently refers to a set of concepts for distributed and disaggregated operations centered heavily on short notice and otherwise irregular deployments, often to remote, austere, or otherwise non-traditional locales. The APU issue is the latest in a long string of problems for the Pegasus, both systemic and incidental. Last week, we told you about a KC -46 that lost its boom during an incident off the coast of Virginia. The Pegasus had been on a F-22 Raptor fighters refueling mission at the time. You can see images of the aftermath of that mishap below. Posted to the Air Force amn/nco/snco Facebook page. This is the KC-46 that landed at Seymour-Johnson after the accident the other day. — Steven Fortson (@zaphod58) July 12, 2025 The recent incident is one of several involving KC-46 booms. Last year, another Pegasus lost its boom while refueling an F-15E Strike Eagle off the coast of California last year. The boom and the control system for it have been a source of serious and persistent technical issues for the Pegasus fleet for years now. A fix for the KC-46's particularly troublesome remote vision system (RVS), which boom operators in the tanker's main cabin use to perform their work, is now unlikely to be finished before summer 2027, roughly three years behind schedule, according to Defense News. The APU problems come as the KC-46 fleet has been in heavy use. Last month, they were part of an armada of refuelers, which also included the KC-135 Stratotankers, which took part of the U.S. buildup of forces in the region as tensions with Iran rose to a fever pitch. They helped refuel the B-2 Spirit stealth bombers that struck Iranian nuclear sites during Operation Midnight Hammer last month. The bombers dropped 14 30,000-pound GBU-57/B Massive Ordnance Penetrator (MOP) bunker buster bombs on Iran's Fordow and Natanz nuclear facilities. It marked the first combat use of those weapons. We reached out to Air Mobility Command Monday evening to find more details about the APU curtailment and will update this story with any pertinent information provided. In the meantime, the Air Force is working to fix yet another problem on its newest tanker. Contact the author: howard@
India Gazette
12-07-2025
- Politics
- India Gazette
Deployment of RAT indicates engine failure: Commercial Pilot Rajiv Pratap Rudy on Air India plane crash report
New Delhi [India], July 12 (ANI): Commercial Pilot and Bharatiya Janata Party (BJP) leader Rajiv Pratap Rudy on Saturday said that the deployment of Ram Air Turbine (RAT) and the start of Auxiliary Power Unit (APU) operations in the crashed Air India flight 171 indicates towards engine failure. 'It's a preliminary report. In the first stage report, the government is coming out with the facts of what happened inside the aircraft. The facts are that the aircraft ran up to a speed that is required for takeoff, which is called the rotation speed. It lifted from the ground. It went up to the speed of 180 knots, which is a good acceleration speed. And possibly after that, technically, 2 or 3 things have happened. One is the deployment of RAT, which has happened, and the second is that the APU, auxiliary power unit, has started operations,' Rudy told ANI. He added that the fuel switches were found at the run position in the report, which is recommended to do when the aircraft starts losing control. 'This automatically happens in an aircraft when there is a twin-engine failure. So this, as indicated in the report, has happened, and both the initial stages of APU have started, and the RAT has deployed, so it indicates the engine failure has taken... When you start losing the aircraft, the pilot monitoring the situation immediately puts the fuel switch control off and instantly puts it back on. After the crash, both switches were found on,' Rudy said. The AAIB's Preliminary Report, released on Friday, said that both the engines of the aircraft were moved from 'run' to 'cutoff' in quick succession, which resulted in the fuel supply being cut off. The report says that in the cockpit voice recording, one of the pilots is heard asking the other why he did the cutoff, which the other pilot denied ever doing so. 'The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC, and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off,' the preliminary report said. 'In the cockpit voice recording, one of the pilots is heard asking the other why he cut off. The other pilot responded that he did not do so,' the report added. As per the Enhanced Airborne Flight Recorder (EAFR) accessed by the AAIB, engine 1's fuel cut switch transitioned from 'cutoff' to 'run' at about 8:08:52 UTC (Coordinated Universal Time), and at 8:08:56 UTC, Engine 2's fuel switch also went from 'cutoff' to run'. According to the report, just 13 seconds later, at 8:09:05 UTC, one of the pilots transmitted the Mayday call, which the Air Traffic Control Officer (ATCO) enquired about, but did not receive a reply. Shortly after, the aircraft was observed crashing outside the airport boundary, and the emergency response was activated. The Airline Pilots' Association of India on Saturday also called for a 'fair, fact-based inquiry' into the incident and rejected the 'tone and direction of the investigation', which suggested a bias towards pilot error. 'The report was leaked to the media without any responsible official signature or attribution. There is a lack of transparency in investigations as investigations continue to be shrouded in secrecy, undermining credibility and public trust. Qualified, experienced personnel, especially line pilots, are still not being included in the investigation team,' the association said in a statement. Notably, Minister of State for Civil Aviation Murlidhar Mohol urged people not to draw conclusions based on the preliminary report. While speaking to mediapersons, the MoS said, 'The AAIB has brought out a preliminary report. This is not the final report. Until the final report comes out, we should not arrive at any conclusion. AAIB is an autonomous authority, and the ministry does not interfere in their work.' (ANI)
India Today
12-07-2025
- General
- India Today
Seconds before Mayday, Air India fuel switches turned back from 'cutoff' to 'run'
Thirteen seconds before Air Traffic Control received the 'MAYDAY' call from the Ahmedabad-London AI171 Dreamliner on the day of the crash, June 12, a preliminary probe by the Civil Aviation Ministry revealed that the fuel control switches were being transitioned back from 'CUTOFF' (fuel stopped) to 'RUN' (fuel flowing).According to the Aircraft Accident Investigation Bureau (AAIB), both engines of the ill-fated aircraft experienced a momentary recovery after an initial loss of thrust, but ultimately failed to stabilise. The crash ultimately led to the deaths of 260 the first engine's core deceleration stopped, reversed, and began to recover, the second engine could not arrest its deceleration, according to the AAIB's report released today, a month after the crash. According to the recording from the Enhanced Airborne Flight Recorder (EAFR) accessed by AAIB, the Civil Aviation Ministry's investigative arm revealed that the fuel cutoff switch of the first engine transitioned from "CUTOFF" to "RUN" at about 08:08:52 seconds later, the Auxiliary Power Unit (APU) inlet door began to open during takeoff, which could disrupt airflow, according to several experts. The APU provides electrical and pneumatic power while the aircraft is on the ground, and occasionally in the two seconds, the Engine 2 fuel cutoff switch also transitioned from "CUTOFF" to "RUN."Engine 1's core deceleration stopped, reversed and started to progress to recovery, according to the preliminary probe 2 was able to relight but could not arrest core speed deceleration and re-introduced fuel repeatedly to increase core speed acceleration and recovery, the report further stated.- Ends
Hindustan Times
12-07-2025
- General
- Hindustan Times
AAIB report reveals Air India flight AI171's both engines shut down seconds after take-off on June 12
India's Aircraft Accident Investigation Bureau or AAIB has released the preliminary report into the tragic crash of Air India flight AI171, a Boeing 787-8 aircraft, which crashed shortly after takeoff from Ahmedabad's Sardar Vallabhbhai Patel International Airport on June 12. People look at the debris of the Air India plane that crashed moments after taking off from the airport, in Ahmedabad on June 12.(PTI) In the report, released shortly after midnight on Saturday, one of the findings shows both engines of the Air India Dreamliner shut down mid-air just seconds after take-off. According to the AAIB's findings on the Boeing 787-8 crash — which claimed 260 lives, including 241 of the 242 people on board — the fuel cutoff switches that regulate fuel supply to the engines shifted from the 'RUN' to the 'CUTOFF' position almost simultaneously, within a second of each other. Also Read | Ahmedabad Air India plane crash initial probe report shows fuel cutoff to both engines Significantly, the cockpit voice recorder captures one pilot asking, 'Why did you cut off?' to which the other responds, 'I didn't.' 'As per the EAFR (Enhanced Airborne Flight Recorder), the Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN at about 08:08:52 UTC. The APU Inlet Door began opening at about 08:08:54 UTC, consistent with the APU Auto Start logic. Thereafter at 08:08:56 UTC the Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN. When fuel control switches are moved from CUTOFF to RUN while the aircraft is inflight, each engines full authority dual engine control (FADEC) automatically manages a relight and thrust recovery sequence of ignition and fuel introduction,' the preliminary report said. Also Read | 'Mayday' call, then silence: AAIB probe reveals moments before Air India crash in Ahmedabad This uncommanded shutdown triggered the deployment of the Ram Air Turbine (RAT), and the aircraft began losing altitude almost immediately, unable to sustain powered flight. According to the AAIB, the pilots re-engaged the fuel switches in an attempt to relight both engines. Engine 1 showed signs of recovering thrust, but Engine 2 failed to stabilise. The aircraft, which had briefly reached a speed of 180 knots, was already descending and failed to regain altitude. The final distress call – a "MAYDAY" – was transmitted at 08:09 UTC, just seconds before the aircraft crashed into residential buildings outside the airport perimeter. Also Read | 'Why did you cut off ?': Cockpit recording reveals what Air India pilots said before Ahmedabad crash The Air India aircraft slammed into several buildings, including the BJ Medical College hostel, sparking fires and causing serious structural damage to at least five structures. Wreckage from the crash was strewn across more than 1,000 feet. Major parts of the plane — including the engines, landing gear, and vertical stabiliser — were found either embedded in buildings or scattered around the area. The plane, registered as VT-ANB, had been in service since 2013 and had recently cleared routine maintenance checks. Investigators confirmed that all Airworthiness Directives were complied with, the fuel met quality standards, and there were no signs of any technical glitches in the engines or flight control systems leading up to the crash. The pilot-in-command, 56-year-old captain Sumeet Sabharwal, with over 15,000 flying hours, and co-pilot Clive Kunder, 32, with over 3,400 hours, were both fully qualified and had no recent duty irregularities or medical issues reported.
Rhyl Journal
12-07-2025
- General
- Rhyl Journal
Fuel switches cut off before Air India crash, preliminary report says
The Boeing 787 Dreamliner crashed shortly after take-off on June 12 in what is one of the deadliest plane accidents in terms of the number of British nationals killed. The report from the Aircraft Accident Investigation Bureau, published late on Friday, said the jet was carrying 54,200kg of fuel, which was within the 'allowable limits'. The report then said: 'The aircraft achieved the maximum recorded airspeed of 180 Knots IAS at about 08:08:42 UTC and immediately thereafter, the Engine 1 and Engine 2 fuel cutoff switches transitioned from RUN to CUTOFF position one after another with a time gap of 01 sec. The Engine N1 and N2 began to decrease from their take-off values as the fuel supply to the engines was cut off. 'In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff. The other pilot responded that he did not do so.' Referring to data recovered from the plane's two Enhanced Airborne Flight Recorders (EAFR), it went on: 'As per the EAFR, the Engine 1 fuel cutoff switch transitioned from CUTOFF to RUN at about 08:08:52 UTC. The APU Inlet Door began opening at about 08:08:54 UTC, consistent with the APU Auto Start logic. 'Thereafter, at 08:08:56 UTC the Engine 2 fuel cutoff switch also transitions from CUTOFF to RUN. When fuel control switches are moved from CUTOFF to RUN while the aircraft is inflight, each engine's full authority dual engine control (FADEC) automatically manages a relight and thrust recovery sequence of ignition and fuel introduction.' While the engines started to recover, one of the pilots transmitted 'mayday, mayday, mayday' before the jet was observed by air traffic control to crash outside the airport. Some 241 people on board were killed in the crash and one passenger survived, while 19 other people also died and 67 were seriously injured. The plane crashed and struck a medical college hostel in a residential part of Ahmedabad. The report states: 'The aircraft was destroyed due to impact with the buildings on the ground and subsequent fire. 'A total of five buildings were impacted and suffered major structural and fire damages.' The only surviving passenger was Briton Vishwash Kumar Ramesh, who previously told The Sun it was a 'miracle' he was alive but felt 'terrible' he could not save his brother Ajay. Both pilots, who were based at Mumbai and had arrived in Ahmedabad the previous day, had taken an 'adequate rest period' before the flight. The crew, who had been given a breath analyser test earlier, were recorded as fit to operate the flight. No significant bird activity was spotted near the flight path and the aircraft started to lose altitude before crossing the airport perimeter wall. Both engines were retrieved from the wreckage and quarantined at a hangar in the nearby airport. Investigators have identified 'components of interest for further examinations,' the report says. Fuel samples that were taken from tanks used to refuel the aircraft were 'satisfactory'. The report added: 'Very limited amount of fuel samples could be retrieved from the APU filter and Refuel/Jettison valve of the left wing. 'The testing of these samples will be done at a suitable facility capable of carrying out the test with the limited available quantity.' Statements have been taken from Mr Ramesh and witnesses by the investigators, who will also be looking at the post-mortem reports of the crew and the passengers. This is being done 'to corroborate aeromedical findings with the engineering appreciation,' the report adds. An Air India spokesman said: 'Air India stands in solidarity with the families and those affected by the AI171 accident. We continue to mourn the loss and are fully committed to providing support during this difficult time.' The spokesman added: 'Air India is working closely with stakeholders, including regulators. 'We continue to fully co-operate with the Aircraft Accident Investigation Bureau (AAIB) and other authorities as their investigation progresses. 'Given the active nature of the investigation, we are unable to comment on specific details and refer all such enquiries to the AAIB.'
