Go Back  PPRuNe Forums > Aircrew Forums > Rotorheads
Reload this Page >

Zephire helicopter parachute

Rotorheads A haven for helicopter professionals to discuss the things that affect them

Zephire helicopter parachute

Old 13th Jan 2019, 16:34
  #21 (permalink)  
 
Join Date: Jun 2016
Location: Brantisvogan
Posts: 449
What is the rate of descent under the chute?
Even on the cirrus you can do yourself an injury pulling the lever.
Bell_ringer is online now  
Old 13th Jan 2019, 22:58
  #22 (permalink)  
 
Join Date: Sep 2006
Location: Inside the Industry
Posts: 682
This is a well questioned path on this forum. To operate single-engined over "hostile" terrain requires a number of mitigations to be in place to reduce the risk in the event of an engine failure. Commercial or Military operators are very familiar with these, and again I would be fascinated in the data that shows an engine failure (or drive issue) at altitude that can't be managed with a correctly executed autorotation, including zero speed onto rugged terrain. The main risk mitigation for non-commercial operations should be not to operate over "hostile" terrain unless absolutely imperative
Hence my quotation marks around the word hostile. Although operations by professoinals over hostile areas must be mitigated and engine failures are rare, we see SE helicopters flying at night on EMS missions over built up areas, I often see smaller private helicopters being flown with low regard for where they might land if it all goes quiet. Add the potential difficulty of achieving a successful autorotation and EOL in the heat of the moment for many leisure pilots then is a great idea worth developing.
industry insider is offline  
Old 13th Jan 2019, 23:49
  #23 (permalink)  
 
Join Date: Sep 2017
Location: Canada
Posts: 259
I like the concept, its a viable safety feature in some instances, but I'm skeptical it would ever work effectively on anything larger and heavier
GrayHorizonsHeli is offline  
Old 14th Jan 2019, 04:21
  #24 (permalink)  
 
Join Date: Apr 2009
Location: halifax
Age: 53
Posts: 16
motor, rotor, ball....uhhhh,,,deploy....
Back door is offline  
Old 16th Jan 2019, 15:50
  #25 (permalink)  
 
Join Date: Nov 2007
Location: Massachusetts
Age: 62
Posts: 124
I gotta say I'm a bit negative about parachute systems for aircraft, although one of the instructors at our school popped the chute in a Cirrus after an engine failure over non-hospitible terrain and she seems to like it

My question is what's the deal with mounting it to the mast? Seems like it would have made more sense to mount it to the cabin structure so that if the mast/rotor decided to leave and go away that the parachute would stay with the aircraft?

What I've always wondered is why we can do the giant airbag thing like the Mars Exploration Rover and Mars Pathfinder used? Just how big an airbag would a S92 require?
Paul Cantrell is offline  
Old 16th Jan 2019, 20:41
  #26 (permalink)  
 
Join Date: May 2010
Location: PNW
Posts: 73
Originally Posted by Paul Cantrell View Post
My question is what's the deal with mounting it to the mast? Seems like it would have made more sense to mount it to the cabin structure so that if the mast/rotor decided to leave and go away that the parachute would stay with the aircraft?
Where else would you put it, where it wouldn't be snagged by the main or tail rotors? It does depend on the mast and rotor head surviving, but complete departure is fairly rare. This is designed for the most likely scenarios, not every possible scenario.

Aside from clearing the rotor, that location guarantees an upright (or nearly upright) landing, where the undercarriage might absorb some of the shock, and some seats are designed to collapse vertically if it's a rough parachute touchdown. The occupants also have the best chance of exiting safely if the helicopter is upright, especially if ditching in water. It's why Cirrus locates their ballistic parachute at, or near the C.G. as well. I still think it's not a great idea, and it sure isn't going to help the aerodynamics. But the location seems sound to me.

What I've always wondered is why we can do the giant airbag thing like the Mars Exploration Rover and Mars Pathfinder used? Just how big an airbag would a S92 require?
Well for a start, Mars has 38% of Earth's gravity, so the dyamics are a wee bit different! Those landers are also designed to survive high G-loads.

On Earth, an air bag wouldn't do anything a successful autorotation wouldn't accomplish. In a situation where an auto isn't possible -- like that awful Leicester City crash -- I don't think any airbag of reasonable size and weight would have cushioned the landing enough for survival. Not from that height. A ballistic parachute might have worked, but it would have to be huge, and fired immediately. I think that accident happened around the minimum altitude for this smaller system to be effective.
Photonic is offline  
Old 16th Jan 2019, 23:43
  #27 (permalink)  
 
Join Date: Sep 2017
Location: Canada
Posts: 259
Originally Posted by Paul Cantrell View Post
Just how big an airbag would a S92 require?
Cue the Yo Momma jokes....LOL
GrayHorizonsHeli is offline  
Old 17th Jan 2019, 05:28
  #28 (permalink)  
 
Join Date: Sep 2002
Location: Great South East, tired and retired
Posts: 2,244
A helicopter heavy landing/crash usually involves multiple bounces/rolls on the ground. An airbag inflates quickly and deflates almost as quickly, so no protection for the second and subsequent bounces.

It would also probably push the cyclic back at the pilot's delicate areas, rather forcefully, and also breaking the right wrist.
Ascend Charlie is offline  
Old 17th Jan 2019, 19:49
  #29 (permalink)  
 
Join Date: May 2002
Location: "Deplorable but happy as a drunken Monkey!
Age: 70
Posts: 16,065
It does depend on the mast and rotor head surviving, but complete departure is fairly rare.

Statistically for most but hot all....of late.
SASless is offline  
Old 15th Apr 2019, 18:19
  #30 (permalink)  
 
Join Date: Dec 2014
Location: Africa
Posts: 306
Vertical Magazine article: https://www.verticalmag.com/news/cur...utm_content=V1

Although the test was performed from 300 meters, based on the results, Curti believes the parachute could be successfully deployed at any altitude over 150 meters (500 feet), or possibly even lower if the aircraft carries some forward speed.

The design team made the decision to stop the rotation of the main rotor blades as part of the parachute deployment sequence. This was for two reasons: first, to avoid airflow disruptions that could slow the opening of the parachute, and also to reduce the risk of injury at touchdown.

“What we have observed in helicopter crashes is that often most of the casualties are created by the rotor blades that are out of control,” Cantelli explained. “So we think that if you cannot perform autorotation for any reasons, it is better to touch the ground without any rotating blade.”

In the remotely piloted test, this stoppage was accomplished through a deliberate series of steps. The engine was cut off, the collective was raised to decrease main rotor RPM, and then the rotor brake was applied before the parachute was ejected. However, Curti plans to make this sequence automatic in the version of the system that is made available to customers. “We will have a very simple lever that will activate everything, but with no sensor activation, so it will always be at the choosing of the pilot,” Albertazzi said.
Hot and Hi is offline  
Old 16th Apr 2019, 14:24
  #31 (permalink)  
 
Join Date: Feb 2005
Location: On the green bit near the blue wobbly stuff
Posts: 590
Originally Posted by Hot and Hi View Post
So...... A system which automatically shuts down the engine, raises the collective and puts the rotor brake on in flight. ( And then hopes to deploy the parachute. )
Any volunteers?
Non-PC Plod is offline  
Old 18th Apr 2019, 21:13
  #32 (permalink)  
MLH
 
Join Date: Aug 2006
Location: California
Posts: 43
Forget the parachute, I want the full sized RC model.
MLH is offline  
Old 18th Apr 2019, 21:31
  #33 (permalink)  
 
Join Date: Apr 2003
Location: USA
Posts: 72
Originally Posted by Non-PC Plod View Post
So...... A system which automatically shuts down the engine, raises the collective and puts the rotor brake on in flight. ( And then hopes to deploy the parachute. )
Any volunteers?
sure so long as initiation height is 10,000’+ft AO and no door installed and wearing your own parachute with skyhook.
havick is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.