cirrus sr22
Join Date: Oct 2006
Location: Bristol
Posts: 117
Likes: 0
Received 0 Likes
on
0 Posts
Rate of descent without parachute
Interesting article in AVweb ("Fun With Parachute Mode") about the rate of descent in a DA40 with the trim right back and throttle at idle (stalled 'phugoid' mode ?), being in the same order as the Cirrus with the parachute deployed, albeit with the DA40 having 48kts forward velocity.
Parachute in a Plane
In which case does the parachute buy you much?
The article also mentions other planes that can do similar 'parachute mode' ?
Parachute in a Plane
In which case does the parachute buy you much?
The article also mentions other planes that can do similar 'parachute mode' ?
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,598
Likes: 0
Received 0 Likes
on
0 Posts
Read the article, then read comment #3, by the author:
This means that you have to be able to keep the wings level to start with. So in a spin, you've got to recover from the spin first anyway. And in IMC, you are now trying to keep the wings level on instruments while the aircraft is bucking every which way. (Assuming that the instruments work in the first place - if you have an engine failure in IMC you also lose vacuum pressure and thus the AH and DI.)
I like the DA40 but to suggest that this parachute mode is a direct contender to the Cirrus CAPS system is a bit over the top, I think.
You do have to keep the wings level with rudder or aileron.
I like the DA40 but to suggest that this parachute mode is a direct contender to the Cirrus CAPS system is a bit over the top, I think.
Join Date: May 2001
Location: UK
Posts: 4,631
Likes: 0
Received 0 Likes
on
0 Posts
It would be interesting to know whether Diamond have included any design features to reduce the energy transmitted in a "vertical" descent - I suspect not. Cirrus have done so and therefore in terms of the energy transmitted to the POB I suspect the two are less than comparable.
In the event of a forced landing I think the author and Diamond should be careful about making out the POB are likely to have the same "protection" that a CAPS descent in a Cirrus might afford although over the "wrong" terrain and in the "right" weather conditions it just might be a better option than a conventional forced landing.
In the event of a forced landing I think the author and Diamond should be careful about making out the POB are likely to have the same "protection" that a CAPS descent in a Cirrus might afford although over the "wrong" terrain and in the "right" weather conditions it just might be a better option than a conventional forced landing.
Join Date: May 2010
Location: Germany
Posts: 73
Likes: 0
Received 0 Likes
on
0 Posts
Hi,
48kt are 48kt are 48 kt... are 48kt you have to de-energize when hitting any structure, no matter if it's a corn field, a tree or a brick wall.
I would always (!) favor the parachute over the high angle approach with minimum forward movement.
About the crash resistance: there has been a C182 (old generation) crash a few weeks ago with minor injuries. There doesn't seem to be much need for a crumple zone when a chute is being installed. Good to have, but not essential as it seems.
I'm stunned that the BRS retrofit for the C172 and C182 models is chosen by so few - for the price of some avionics gimmicks and with only 25kg or so weight penalty one can save ones life (and their loved ones') in so many cases of spatial disorientation, midlife collisions, incapitation and so on... (no, I don't have any connection with BRS to praise their products, but the BRS chute discussion has some similarity with the seat belt discussions in the 70s and 80s...)
Kind regards,
Peter
48kt are 48kt are 48 kt... are 48kt you have to de-energize when hitting any structure, no matter if it's a corn field, a tree or a brick wall.
I would always (!) favor the parachute over the high angle approach with minimum forward movement.
About the crash resistance: there has been a C182 (old generation) crash a few weeks ago with minor injuries. There doesn't seem to be much need for a crumple zone when a chute is being installed. Good to have, but not essential as it seems.
I'm stunned that the BRS retrofit for the C172 and C182 models is chosen by so few - for the price of some avionics gimmicks and with only 25kg or so weight penalty one can save ones life (and their loved ones') in so many cases of spatial disorientation, midlife collisions, incapitation and so on... (no, I don't have any connection with BRS to praise their products, but the BRS chute discussion has some similarity with the seat belt discussions in the 70s and 80s...)
Kind regards,
Peter
Join Date: Feb 2001
Location: US
Posts: 604
Likes: 0
Received 0 Likes
on
0 Posts
In which case does the parachute buy you much?
The point of the parachute is for when you've lost control. And if you've lost control, then how are you going to get into that controlled attitude?
If you lose control at low altitude, it seems to my uneducated mind that you might be able to pull the parachute handle in time, but that you are highly unlikely to be able to get the aircraft into that controlled, nose-up mode that the author speaks about.
Join Date: May 2001
Location: UK
Posts: 4,631
Likes: 0
Received 0 Likes
on
0 Posts
Maybe, (with regards spin training) but some of these aircraft havent demonstrated spin recovery during their certification and like many things i am not convinced of the value of training unless it is cojoined with currency. I still fly aeros enough but i know after a few months of missing them a deliberate spin is still interesting - then again i am probably just getting old. Still if push comes to shove i would prefer the pilot pulls the handle than rely on a few hours of spin training five years ago.
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,598
Likes: 0
Received 0 Likes
on
0 Posts
Just wondering. How many CAPS deployments in recent years were done due to inadvertent spins? I can't remember any, but then again I'm not keeping a detailed track of this.
The deployments I can remember were mostly loss-of-control in IMC and in one instance an incapacitated pilot whose wife deployed the CAPS instead of risking to fly the aircraft to a landing.
In any case, the place where you are most likely to spin due to mishandling is somewhere on base/final and in that situation both spin training and CAPS has a value of exactly zero.
The deployments I can remember were mostly loss-of-control in IMC and in one instance an incapacitated pilot whose wife deployed the CAPS instead of risking to fly the aircraft to a landing.
In any case, the place where you are most likely to spin due to mishandling is somewhere on base/final and in that situation both spin training and CAPS has a value of exactly zero.
Join Date: May 2001
Location: UK
Posts: 4,631
Likes: 0
Received 0 Likes
on
0 Posts
I dont recall a caps deployment following a spin but it is a conceivable scenario. Even at low level there is some suggestion a caps partial deployment can help assuming of course the pilot reacts quickly enough. Some suggested the pilot that suffered an efato at staverton might have benefited by pulling the chute; he didnt so it is speculation.
Join Date: Sep 2002
Location: Garstang, Preston, UK
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
Cirrus ab initio training
Thanks for the link to JPM Aviation, baldwinm, unfortunately they are unable to offer PPL training :-(
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,598
Likes: 0
Received 0 Likes
on
0 Posts
Even at low level there is some suggestion a caps partial deployment can help
Join Date: May 2001
Location: UK
Posts: 4,631
Likes: 0
Received 0 Likes
on
0 Posts
I gather you might get full deployment in as little as 400 feet.
Even with a partial deployment I guess the drag would have a significant impact on forward velocity.
It does raise the sole searching question in the event of an EFATO at what height you might pull the chute, discussed on many occasions on COPA. I suspect every pilot must reach their own conclusions taken together with the circumstances of the pull.
The Cirrus does have some useful features to help reduce injury caused by forward velocity including in belt air bags and a crumple zone.
I was looking very recently at the remains of the cockpit of a Cirrus that suffered an EFATO; the passenger compartment survived extraordinarily well in the circumstances disregarding for a moment the fire damage.
Even with a partial deployment I guess the drag would have a significant impact on forward velocity.
It does raise the sole searching question in the event of an EFATO at what height you might pull the chute, discussed on many occasions on COPA. I suspect every pilot must reach their own conclusions taken together with the circumstances of the pull.
The Cirrus does have some useful features to help reduce injury caused by forward velocity including in belt air bags and a crumple zone.
I was looking very recently at the remains of the cockpit of a Cirrus that suffered an EFATO; the passenger compartment survived extraordinarily well in the circumstances disregarding for a moment the fire damage.
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,598
Likes: 0
Received 0 Likes
on
0 Posts
Even with a partial deployment I guess the drag would have a significant impact on forward velocity.
In addition to this, somebody mentioned that if you're sitting more or less upright, and are properly strapped in, your body can sustain 50G in the horizontal, but only 15G or so in the vertical, because your spine is relatively weak in compression. I haven't done the sums (and they would depend on the size of the horizontal and vertical crumple zone anyway) but based on this it may well be that crashing horizontally into something at stall speed is more survivable than crashing vertically into something under a partially inflated chute. (But I'll take a fully inflated chute over an unrecovered spiral dive any day!)
So my gut feeling tells me that using the chute in an EFATO situation, when you are below the altitude for full deployment, might actually worsen the situation. Compared to gliding the plane to a more-or-less suitable landing spot.
But I'm not a Cirrus pilot or owner, and all I know about the CAPS system is from what I read on here. I would certainly hope that the Cirrus type-specific training that is on offer (and, I understand, is mandated by insurance companies) would go into the deployment of CAPS, including when NOT to deploy it. Just like turning back to the airfield or not, in an EFATO situation.
(Edited: It's PPRuNe that feels the need to explain the E-F-A-T-O abbreviation every time, not me.
)
Join Date: Nov 2010
Location: South England
Posts: 56
Likes: 0
Received 0 Likes
on
0 Posts
In addition to this, somebody mentioned that if you're sitting more or less upright, and are properly strapped in, your body can sustain 50G in the horizontal, but only 15G or so in the vertical, because your spine is relatively weak in compression. I haven't done the sums (and they would depend on the size of the horizontal and vertical crumple zone anyway) but based on this it may well be that crashing horizontally into something at stall speed is more survivable than crashing vertically into something under a partially inflated chute.
I remember when former Formula 1 driver David Purley crashed his car in the late '70's and a quick google search has shown this was a 179G crash and he survived
- perhaps aircraft designers could learn a lesson about building light weight but strong energy absorbing airframe 'tubs' from the motor racing brigade!As we all know, it's not the fall that hurts, but the sudden stop at the end
Join Date: Feb 2007
Location: Amsterdam
Posts: 4,598
Likes: 0
Received 0 Likes
on
0 Posts
does the Cirrus have anything similar?
Join Date: Apr 2006
Location: uk
Age: 63
Posts: 714
Likes: 0
Received 0 Likes
on
0 Posts
VJMEHRA call John Page at Cirrus Aircraft & Glass Cockpit Training | Cirrus Aircraft Rental
They are in Denham, have SR20 and SR22 and do a lot of the UK transition training.
John is "probably" the most experienced Cirrus instructor in the UK
In theory they can do Ab Initio so worth a call
They are in Denham, have SR20 and SR22 and do a lot of the UK transition training.
John is "probably" the most experienced Cirrus instructor in the UK
In theory they can do Ab Initio so worth a call
Join Date: Dec 2008
Location: San Diego, CA, USA
Posts: 115
Likes: 0
Received 0 Likes
on
0 Posts
As for CAPS pulls after a spin, yes, the Indianapolis, IN, accident in 2006 involved a 3-1/2 turn spin (NTSB report here).
The flight data was recovered from the avionics. The plane was in the spin for over 15 seconds and had been in a mushed state for 30 more seconds prior to that. The parachute activation was determined to be at 528' AGL, just 4 seconds prior to impact into a shallow pond. The recorded data showed that the airspeed declined from 100 knots to 67 knots in those 4 seconds. The pilot died from blunt force trauma to the head. The activation was done by the pilot's son in the right seat after the pilot's wife in the back seat suggested the parachute at least 3 times, according to the witness interviews with the accident investigator.
Just 4 seconds earlier and the impact would likely have been at 17 knots and survivable.
Cheers
Rick
Join Date: Dec 2008
Location: San Diego, CA, USA
Posts: 115
Likes: 0
Received 0 Likes
on
0 Posts
Another high-speed deployment at 187 KIAS in a 4000 fpm spiral dive lost about 400' altitude. Interesting that the faster airspeed resulted in a faster deployment.
Cheers
Rick