Can an EC135 do a roll or loop

Joined: Jul 2014
Posts: 548
Likes: 62
From: England
Please forgive an ignorant question – I know very little of the subtleties of rotary flying – but if it's possible to do a 1G barrel roll in a fixed-wing, isn't it possible to do a 1G barrel roll in a helicopter without stressing either the airframe or the moving parts?

Joined: Jun 2006
Aviation Qualifications: ATP+Mil
Posts: 957
Likes: 786
From: 350/3 Compton
You have probably seen this old video - I wouldn't like being the next up in that one!
https://www.youtube.com/watch?v=s4xZIg6NNkw
https://www.youtube.com/watch?v=s4xZIg6NNkw
Mog


Joined: Oct 1999
Aviation Qualifications: ATPL
Posts: 7,371
Likes: 926
From: Den Haag
Please forgive an ignorant question – I know very little of the subtleties of rotary flying – but if it's possible to do a 1G barrel roll in a fixed-wing, isn't it possible to do a 1G barrel roll in a helicopter without stressing either the airframe or the moving parts?

Joined: Apr 2000
Aviation Qualifications: ATP+Mil
Posts: 10,959
Likes: 1,814
From: EGDC
Please forgive an ignorant question – I know very little of the subtleties of rotary flying – but if it's possible to do a 1g barrel roll in a fixed-wing, isn't it possible to do a 1G barrel roll in a helicopter without stressing either the airframe or the moving parts?

Joined: Nov 2006
Posts: 1,951
Likes: 90
From: After all, what’s more important than proving to someone on the internet that they’re wrong? - Manson
It isn't possible to do a 1 g barrel roll in a FW - it's a myth that is perpetuated, and defies the basic laws of physics and motion!
Aero's in a helicopter can be done "within limits" - the issue is Joe Pilot doesn't know what they are as the manufacturer or certification authority does not publish them.
Test pilots are called "test pilots" for a reason and they come in different flavours - Production and Experimental. Production Test are pretty much average Joe and Experimental Test live a bit closer to God than most!
Helicopters mostly if any do not have a large enough thrust margin to create high g loadings. They will just mush or wash off speed.
It's the other bits that most people don't think about that are the issue that maybe cannot keep up with what the aircraft "could do".
i.e. precession loads on the TR, feedback to the MR PCL's, Low or prolonged -ve g on lube, fuel and HYD systems and the list goes on.
For example - everybody knows about HYD "jack stall" in an AS350. Why is it that way? It is to give you a built in warning that you are approaching the feedback limits of the PCL's on the MR.
Dual HYD models have a LIMIT light as the warning as they will not "stall". What happens if you go past the "LIMIT"?. You probably will start bending and breaking stuff.
Operating outside the approved envelope is the territory of ETP's. Joe Pilot doing this stuff proves what exactly? You get away with it once, you get away with twice you get away with it...................................?

Joined: Jul 2011
Posts: 187
Likes: 37
From: N/A

Joined: Sep 2007
Posts: 368
Likes: 21
From: I am not sure where we are, but at least it is getting dark


Joined: Oct 1999
Aviation Qualifications: ATPL
Posts: 7,371
Likes: 926
From: Den Haag
All you can tell from the Hoover video is that is positive G, but not how much. It is theoretically possible to maintain a minimum of 1G during the maneuver, but then you will have a maximum of well over 1G towards the end, as you will be in a rapid descent that needs to be arrested.


Joined: Dec 2006
Posts: 431
Likes: 41
From: yes

Joined: Dec 2006
Posts: 1,303
Likes: 23
From: UK and MALTA
I thought this was a “Professional” Pilots rumour network?
Looping and rolling helicopters have no place or requirement when flying professionally. So any wannabes reading the !!!!e posted in this thread………just don’t!11!
All the warnings about rotor and airframe stress forgetting that if the positive g disappears all the fuel, oil and other juices necessary to keep the cab healthy end up in the wrong place.
Moronic Darwinian selection in action.
Looping and rolling helicopters have no place or requirement when flying professionally. So any wannabes reading the !!!!e posted in this thread………just don’t!11!
All the warnings about rotor and airframe stress forgetting that if the positive g disappears all the fuel, oil and other juices necessary to keep the cab healthy end up in the wrong place.
Moronic Darwinian selection in action.

Joined: Apr 2000
Aviation Qualifications: ATP+Mil
Posts: 10,959
Likes: 1,814
From: EGDC
DB - do you know what the g limits for your helicopter are?
Is there a specific warning in the RFM about negative g? (other than for Robbies)
You can get negative g in turbulence - does all the fuel and oil disappear then?
No-one has suggested anyone tries this, it was a question worth asking and answering.
Is there a specific warning in the RFM about negative g? (other than for Robbies)
You can get negative g in turbulence - does all the fuel and oil disappear then?
No-one has suggested anyone tries this, it was a question worth asking and answering.


Joined: Jun 2016
Aviation Qualifications: CPL
Posts: 1,318
Likes: 386
From: Brantisvogan
Originally Posted by [email protected]
DB - do you know what the g limits for your helicopter are?
Is there a specific warning in the RFM about negative g? (other than for Robbies)
You can get negative g in turbulence - does all the fuel and oil disappear then?
No-one has suggested anyone tries this, it was a question worth asking and answering.
Is there a specific warning in the RFM about negative g? (other than for Robbies)
You can get negative g in turbulence - does all the fuel and oil disappear then?
No-one has suggested anyone tries this, it was a question worth asking and answering.
It also looks quite dull, even with Chuck whatsisname in the 105, it's the wrong tool for that job.
If "pulling g" is the objective, choosing rotorcraft will prove disappointing.

Joined: Apr 2000
Aviation Qualifications: ATP+Mil
Posts: 10,959
Likes: 1,814
From: EGDC
I agree Bell_ringer, but DB getting on his high horse about a thread where no-one has suggested just going out and trying such manoeuvres seems rather OTT.
My point to DB was that less than 1g in a helicopter or even negative g doesn't lead to the instant mechanical failure he implied - you can get to negative g without aerobatic manoeuvres as you know.
My point to DB was that less than 1g in a helicopter or even negative g doesn't lead to the instant mechanical failure he implied - you can get to negative g without aerobatic manoeuvres as you know.




