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Can an EC135 do a roll or loop

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Can an EC135 do a roll or loop

Old 17th Jan 2022, 00:36
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Can an EC135 do a roll or loop

With the rotor head on the 135 having no flapping hinge per say but a flexbeam that is outboard of the rotor mast I'd say it has enough authority to do a roll. It will probably create massive stress loads and not something you would want to do more than once before putting the aircraft in the scrap pile but it theory can it be done? Or does anyone have knowledge of airbus flight testing showing that it could or could not be done. This is referencing the crash in Drexel Hill PA with the EC135 and crew reports the aircraft did 2 barrel rolls while on autopilot.
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Old 17th Jan 2022, 02:54
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You can roll anything...just sayin'.
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Old 17th Jan 2022, 03:40
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I was lucky enough in the late 80s to see the AS565 panther do a loop at the factory in Marignane and It was one of the 1st time it was executed live at airshow.
The maneuver was slightly underwhelming as we were all expecting to see a nice round loop, and instead it was basically falling on its tail and recovering.

The point is: in oposition to the BO105 solid machined titaninum head or the lynx all metal head, the AS565 (loop pioneer of the time) is a starflex not as away from the EC 135 flex beams design.


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Old 17th Jan 2022, 04:45
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Looping - probably not a big issue - the 135 has a big hinge offset - watch the mast moment as you fly around and do manoeuvres - nothing much happens compared to the loads you can get on the ground unless you pay attention.

Rolling - Think about the resultant forces - the BO105 suffers in the tail rotor and subsequently i would have my concerns with the EC135 in the area of the ring frame.

Get back to us. I'll put the popcorn on.
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Old 17th Jan 2022, 05:48
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can't you roll anything once?
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Old 17th Jan 2022, 07:43
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Looping and rolling a helicopter puts high stresses on the tail boom and drive shaft - the TR gearbox and hub are big lumps of metal on a long moment arm from the aircraft C of G. Without a g-meter fitted you have little idea what you are doing to the rest of the aircraft.

Could it do it? Sure.

Should it? ........
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Old 17th Jan 2022, 07:51
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I seem to recall Alan Bristow claimed to have looped an FH1100 at Redhill after someone joked "if you loop it, I'll buy one". He did - just - and they didn't... Hope it wasn't the one that crashed at the Paris Airshow...
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Old 17th Jan 2022, 08:11
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Years ago I displayed the Puma HC1. I was encouraged from above to make it a “dynamic” one, rather than previously where displays had consisted of not much more than a series of wing overs, backwards flight and spot turns. As part of my work up I was required to fly with the previous display pilot, who had not displayed for a few years and he showed me manoeuvres that had been developed by himself and others. We subsequently began to explore the capabilities of the aircraft and got to the point where he became slightly nauseous. After that I was left to it.

Shortly afterwards I attended a very interesting brief given by Westlands, who were developing the Lynx and trying hard to impress potential buyers. With a semi rigid head it was a lot more manoeuvrable than my old Puma and it was being “officially” looped and rolled during displays, all very impressive.

However, the Westlands rep stressed that their display aircraft was being very carefully monitored and major components such as main and tail gearboxes were frequently being changed because of the extra stresses put on them. He made it quite clear that a squadron aircraft should definitely not be flown in this way. I realised right then that above all I needed to be gentle and careful with my aircraft to avoid flying it in a way that was potentially more damaging than it was designed for.

Edit: Good advice because with helicopters it’s relatively easy to get into flight regimes that haven’t been taken into account with regard to component fatigue life calculations.

Last edited by ShyTorque; 17th Jan 2022 at 08:56.
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Old 17th Jan 2022, 08:45
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I realised right then that above all I needed to be very gentle and careful with my aircraft to avoid flying it in a way that was potentially more damaging than it was designed for.
Unlike some other Puma pilots I have heard tales about
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Old 17th Jan 2022, 08:45
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…and absolutely not scoring the tail boom with the tail rotor blades….
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Old 17th Jan 2022, 08:51
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EC225 looping:


that absolutely wasn’t flown by the Test Pilot on his last ever flight before retirement, as part of a fly past, in front of the customer whose aircraft it was about to become….
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Old 17th Jan 2022, 08:54
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Originally Posted by PlasticCabDriver View Post
…and absolutely not scoring the tail boom with the tail rotor blades….
PCD,

Definitely not me….and no names mentioned.
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Old 17th Jan 2022, 09:07
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Asking for a friend?
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Old 17th Jan 2022, 11:39
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I can't imagine a more pointless maneuver for a chopper to do.
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Old 17th Jan 2022, 12:04
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If God had meant helos to fly upside down, he would have put the rotor blades underneath!

Mog
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Old 17th Jan 2022, 13:27
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Search on YouTube:
Swiss air force: 20 helicopters in the air
5:30 should be a proof good enough

I am not allowed to post the link
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Old 17th Jan 2022, 16:07
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You have probably seen this old video - I wouldn't like being the next up in that one!
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Old 17th Jan 2022, 17:48
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Originally Posted by Brentd2183 View Post
...
This is referencing the crash in Drexel Hill PA with the EC135 and crew reports the aircraft did 2 barrel rolls while on autopilot.
can you cite a source for this statement?
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Old 17th Jan 2022, 18:10
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The Army Air Corps were looping Gazelles at displays for a number of years before somebody thought to check on whatever passed for the Release To Service in those days. Even the POH clearly stated not to exceed 90 degrees in pitch or roll, but hey, the POH is just like a suggestion, right? I can't remember the exact fallout, but it was quite the task to track down all the airframes that had been looped, and then do the subsequent engineering tear downs to establish how many were bent, buckled or scored. All very embarrassing and quite avoidable. There was also a well known photograph of a Gazelle fully inverted (probably following a roll) against the backdrop of a large TV mast south east of Detmold in Germany, everyone admired it, but nobody ever thought to challenge the how and the why.
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Old 17th Jan 2022, 19:35
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There was also a well known photograph of a Gazelle fully inverted (probably following a roll) against the backdrop of a large TV mast south east of Detmold
I remember seeing one of a Lynx in that position, but not a Gazelle.
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