Genuine question. How does the hot weather (and possibly high altitude) affects the air frame? It will do harm on its engine, but the engine power gets low, so the transmission stress gets lower, and airframe with smaller gross weight will also get less stress?Tempest414 wrote: ↑27 Jul 2023, 11:27We also have to remember that black box that records airframe life this not just flying hours but stress as well so as an idea in Afgan 1 flight hour in the air was about 1.5 on the clock due to hot and high conditions putting extra stress on the airframe
AW101 Merlin Helicopter (RN)
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Re: AW101 Merlin Helicopter (RN)
- Tempest414
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Re: AW101 Merlin Helicopter (RN)
it was a rule of thumb given to me by Apache crews when at Wattisham sometimes it can be lower say 1.2 sometimes higher depends on loads carried
Re: AW101 Merlin Helicopter (RN)
A bit of a generalisation but to keep it simple. Hot and high is the most stressful situation for most aircraft operations as that demands the engines to operating at maximum to lift 1/2 the load as the air is thinner.
Also when in combat zones you are flying tactically much much more which eats up you airframe fatigue hours limit calculations quicker.
Also when in combat zones you are flying tactically much much more which eats up you airframe fatigue hours limit calculations quicker.
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Re: AW101 Merlin Helicopter (RN)
Thanks, understandable for engine, but no damage to airframe.
This will be bad for airframe.Also when in combat zones you are flying tactically much much more which eats up you airframe fatigue hours limit calculations quicker.
So it is two independent things combined.
Re: AW101 Merlin Helicopter (RN)
I've heard helicopters described, amongst other things, as a flying vibration testing machine. If the engine is running harder then so are the rotor blades and between the engines, transmission and rotor blades, the vibration is going to be higher in magnitude and/or higher in frequency, which means more energy per cycle going into the airframe and more cycles in a given period of time.donald_of_tokyo wrote: ↑27 Jul 2023, 13:57 Thanks, understandable for engine, but no damage to airframe.
This means more fatigue damage to the airframe.
Re: AW101 Merlin Helicopter (RN)
Whilst largely about exports, this piece made a mention of Merlin upgrades:
https://www.flightglobal.com/helicopter ... mpaign=RSSIn addition to orders for new-build examples, the UK plant is expected to be bolstered by upgrade work.
Canada has already signed off on the mid-life upgrade of its CH-149 Cormorant fleet – including three new airframes – and Italy is looking to follow suit on its navy’s 22-strong AW101 fleet.
That would see donor parts from the existing fleet incorporated into a new airframe to “make a new 600-series aircraft”, says Higgins.
In addition, the UK has begun initial analysis of a life-extension programme that would see the Royal Navy’s Merlin HM2 and HC4/4A helicopters operated until the early 2040s.
Leonardo Helicopters and Lockheed Martin were commissioned to perform those studies through contracts issued earlier this year.
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- donald_of_tokyo • Poiuytrewq • serge750
"Gentlemen, you can't fight in here! This is the War Room!" - Dr. Strangelove (1964)
Re: AW101 Merlin Helicopter (RN)
And here is the official entry in service with the Polish Navy off their brand new AW101 Merlin helicopter.
( The cammo of the Polish
Navy AW101 Merlin is just perfect )
( The cammo of the Polish
Navy AW101 Merlin is just perfect )
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- Little J • donald_of_tokyo
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Re: AW101 Merlin Helicopter (RN)
UK shall order some 3-6 more AW101s, to
- fill the possible T23ASW gap (Westminster)
- to enable "OSD date extended to 2040", so that "air frames in bad conditions" can be banned without impact on active fleet.
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Re: AW101 Merlin Helicopter (RN)
https://ukdefencejournal.org.uk/c-17-ai ... ddle-east/
The Royal Air Force Air Mobility Force has carried out sorties to recover this year’s exercise equipment from the Middle East, including a Royal Navy helicopter back to the UK just in time for Christmas.
The Royal Navy helicopter, from 845 Naval Air Squadron, is a Merlin MK4 that was loaded onto a 99 Sqn RAF C-17 Globemaster strategic transport aircraft.
The loading, carried out by a combined RAF and RN team, took over 6 hours and was completed as the sun set over the Middle East, ready for the flight to the UK.
According tot he Royal Air Force:
“The RAF Brize Norton based 99 Sqn C-17 Globemaster arrived at its home base in Oxfordshire, where the Merlin will be reassembled and tested. It will then be flown to its home base of Royal Naval Air Station Yeovilton, in Somerset. The sortie was carried out due to the range of a Merlin which would have required multiple through countries adding time, resources, and potential logistical issues. Weighing twice as much as a double decker bus and as high as 3 large artificial Christmas trees, the dismantling of the Merlin for loading onto the C-17 took 5 days to prepare for the flight.”
The Royal Air Force Air Mobility Force has carried out sorties to recover this year’s exercise equipment from the Middle East, including a Royal Navy helicopter back to the UK just in time for Christmas.
The Royal Navy helicopter, from 845 Naval Air Squadron, is a Merlin MK4 that was loaded onto a 99 Sqn RAF C-17 Globemaster strategic transport aircraft.
The loading, carried out by a combined RAF and RN team, took over 6 hours and was completed as the sun set over the Middle East, ready for the flight to the UK.
According tot he Royal Air Force:
“The RAF Brize Norton based 99 Sqn C-17 Globemaster arrived at its home base in Oxfordshire, where the Merlin will be reassembled and tested. It will then be flown to its home base of Royal Naval Air Station Yeovilton, in Somerset. The sortie was carried out due to the range of a Merlin which would have required multiple through countries adding time, resources, and potential logistical issues. Weighing twice as much as a double decker bus and as high as 3 large artificial Christmas trees, the dismantling of the Merlin for loading onto the C-17 took 5 days to prepare for the flight.”
Re: AW101 Merlin Helicopter (RN)
5 days seems a bit sedate. Breaking down a Chinook for a C-17 takes about 10 hours.
Re: AW101 Merlin Helicopter (RN)
Bunch of guys enjoying an all expences paid stay in a warm place, suprising it didn't take longer