Reports of a light aircraft down in Blue Mountains
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Personally, I'd prefer to try escaping a Cirrus coming down on a 'chute in a strong wind - than trying to avoid one coming down at 100kts or more towards me, in a conventional style of crash landing.
1700fpm descent is 31kmh (19.3mph) - and even with a 30kmh wind at ground level (that's pretty breezy), the descent is going to be around an angle of 45 degrees, and probably still less than 40kmh travel speed.
In case no-one noticed in the news reports, there were a group of people gathered for a "home open" real estate inspection, who all scattered when they sighted this Cirrus coming down. No-one has reported being hit by it.
They did report that they were unsure of exactly where it was going to land.
However, they also had time to vacate the LZ because of the relatively low landing speed.
1700fpm descent is 31kmh (19.3mph) - and even with a 30kmh wind at ground level (that's pretty breezy), the descent is going to be around an angle of 45 degrees, and probably still less than 40kmh travel speed.
In case no-one noticed in the news reports, there were a group of people gathered for a "home open" real estate inspection, who all scattered when they sighted this Cirrus coming down. No-one has reported being hit by it.
They did report that they were unsure of exactly where it was going to land.
However, they also had time to vacate the LZ because of the relatively low landing speed.
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What is G force using BRS?
At 1700ft/m and sudden impact I calculate it as being 23 g acting on the aircraft. Load on body would be less than that. Not an engineer so may have that wrong.
Assuming the plane is coming down at 1700 ft/min or 520m/sec and if we assume it starts to decelerate 0.75m from the ground then I calculate you experience 5G (or a deceleration rate of 50m/s/s). I base the 0.75m on a rough estimate of the distance between ground and bottom for cockpit. For the individuals concerned it would be a little less as they have an extra 0.3m of seat slowing them up. Either way it is quite survivable.
Like others I'd like to to know why the engine stopped. The other recent example of a BRS operation was due to the pilot flying for 2 1/2 hours with low oil pressure. I hope the chutes are not encouraging poor judgement.
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considering the terrain in that area, the chute was the better option, unless sure of making Katoomba airstrip. sure, there are a few roads, but lined with light poles, wires, and rail line infrastructure and trees, lots of trees. even after the bushfires that go through there regularly, you think they might consider trimming back a few..
i even get a little worried in my savannah crossing the blue mountains west of here, and i can put it down in 50 to 60 mtrs! then again, if i hold it in a deep stall, it will descend at no more than 1500ft, min. its why its called an aluminium parachute.
i even get a little worried in my savannah crossing the blue mountains west of here, and i can put it down in 50 to 60 mtrs! then again, if i hold it in a deep stall, it will descend at no more than 1500ft, min. its why its called an aluminium parachute.
The biggest trap here is not to just blatantly pop the chute because it is there!
The manufacturer is trying to sell airframes. It is a powerful marketing tool.
The chute is not a get out of gaol free card.
It is just another tool at the pilots' disposal. At the end of the day, the PIC must decide on what they feel is the safest course of action.
The manufacturer is trying to sell airframes. It is a powerful marketing tool.
The chute is not a get out of gaol free card.
It is just another tool at the pilots' disposal. At the end of the day, the PIC must decide on what they feel is the safest course of action.
'Fathy' couldn't agree more there, the chute is just another part of the airframe that has a safety element to it (as well as the obvious commercial advantage) allowing further options (not the only one) if a forced Ldg is req'd.
Wmk2
Wmk2
Last edited by Wally Mk2; 12th May 2014 at 12:20.
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Andy_RR
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So, is anyone experimenting with steerable CAPS systems? Surely given the technology in today's jump parachutes and paragliders etc, it would make some sense to use the technology to improve the glide ratio rather than just opting for an uncontrolled, straight-down approach...?
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So, is anyone experimenting with steerable CAPS systems? Surely given the technology in today's jump parachutes and paragliders etc, it would make some sense to use the technology to improve the glide ratio rather than just opting for an uncontrolled, straight-down approach...?
Oh right. So your real men (tm) are allowed to steer at 140kts, but not at something like 30kts under a canopy?
You have the imagination of a dead ferret, if you can't figure out what advantages forward speed and control might offer.
You have the imagination of a dead ferret, if you can't figure out what advantages forward speed and control might offer.
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You have the imagination of a dead ferret, if you can't figure out what advantages forward speed and control might offer.
Here's where I don't need any imagination, because these are the facts:
- the chute as it is works perfectly in all conceivable aspects of its operation.
- the reasons for chute pulls go far beyond engine failure.
- pilots are the overwhelmingly major cause of accidents. Thus, keeping pilots in control in case of an accident may be a bad idea. The success of the chute (and ejection seats in the military, I might add) certainly points in that direction. That's what my dead-ferret self was trying to convey: We aren't the super-heroes we like to think we are.
We aren't the super-heroes we like to think we are.
I was thinking about this earlier keeping in mind the old fashioned round Army parachutes which I didn't think were steerable.
Then I found this:
How to Steer a Parachute | eHow
Tips & Warnings
Round parachutes are usually not steerable and you have little input on the direction of flight.
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To turn that sized chute I can imagine you would need to pull the "toggles" quite a distance which wouldn't easily be achieved. Hooking it up to the rudder wouldn't give enough throw unless the steering lines were geared.
Interesting question though... I would think it would add complexity that could cause it to all go horribly wrong.
Then I found this:
How to Steer a Parachute | eHow
Tips & Warnings
Round parachutes are usually not steerable and you have little input on the direction of flight.
--------------
To turn that sized chute I can imagine you would need to pull the "toggles" quite a distance which wouldn't easily be achieved. Hooking it up to the rudder wouldn't give enough throw unless the steering lines were geared.
Interesting question though... I would think it would add complexity that could cause it to all go horribly wrong.
You have the imagination of a dead ferret, if you can't figure out what advantages forward speed and control might offer.
Go look up the meaning.
And then *&%# off!
Here's where I don't need any imagination, because these are the facts:
- the chute as it is works perfectly in all conceivable aspects of its operation.
- the reasons for chute pulls go far beyond engine failure.
- pilots are the overwhelmingly major cause of accidents. Thus, keeping pilots in control in case of an accident may be a bad idea. The success of the chute (and ejection seats in the military, I might add) certainly points in that direction.
- the chute as it is works perfectly in all conceivable aspects of its operation.
- the reasons for chute pulls go far beyond engine failure.
- pilots are the overwhelmingly major cause of accidents. Thus, keeping pilots in control in case of an accident may be a bad idea. The success of the chute (and ejection seats in the military, I might add) certainly points in that direction.
Seriously, the BRS works well, but it's pot-luck what you land on top of and what the end result might be. They're also heavy, or, put it another way, if you could increase the effective wing-loading by allowing controlled forward speed, they could be made lighter and as a result be made available and suitable for even more aircraft. Progress be damned, though!
Do PPruners think this incident has improved Cirrus reputation in the marketplace of potential Cirrus buyers, or detracted from it?
Does the demonstration of the BRS over difficult terrain confirm that such an incident is survivable make you want one more?
Or does the fact the engine failed make you want one less?
I note this was a very, very new aircraft, initially granted CofA in January, presumably shipped out, not flown out, to Australia. So must have had very few hours on clock.
Does the demonstration of the BRS over difficult terrain confirm that such an incident is survivable make you want one more?
Or does the fact the engine failed make you want one less?
I note this was a very, very new aircraft, initially granted CofA in January, presumably shipped out, not flown out, to Australia. So must have had very few hours on clock.
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Quoting flying_ted:
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I am an engineer and I think you are wrong Mark.
Assuming the plane is coming down at 1700 ft/min or 520m/sec and if we assume it starts to decelerate 0.75m from the ground then I calculate you experience 5G (or a deceleration rate of 50m/s/s). I base the 0.75m on a rough estimate of the distance between ground and bottom for cockpit. For the individuals concerned it would be a little less as they have an extra 0.3m of seat slowing them up. Either way it is quite survivable.
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Probably you meant 520m/min. Or 8.64 m/sec
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I am an engineer and I think you are wrong Mark.
Assuming the plane is coming down at 1700 ft/min or 520m/sec and if we assume it starts to decelerate 0.75m from the ground then I calculate you experience 5G (or a deceleration rate of 50m/s/s). I base the 0.75m on a rough estimate of the distance between ground and bottom for cockpit. For the individuals concerned it would be a little less as they have an extra 0.3m of seat slowing them up. Either way it is quite survivable.
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Probably you meant 520m/min. Or 8.64 m/sec
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Pearly White
I note this was a very, very new aircraft, initially granted CofA in January, presumably shipped out, not flown out, to Australia. So must have had very few hours on clock.
I note this was a very, very new aircraft, initially granted CofA in January, presumably shipped out, not flown out, to Australia. So must have had very few hours on clock.
I know the ferry team.
Do PPruners think this incident has improved Cirrus reputation in the marketplace of potential Cirrus buyers, or detracted from it?
Does the demonstration of the BRS over difficult terrain confirm that such an incident is survivable make you want one more?
Or does the fact the engine failed make you want one less?
I note this was a very, very new aircraft, initially granted CofA in January, presumably shipped out, not flown out, to Australia. So must have had very few hours on clock.
Well maintained engines very, very, very rarely stop suddenly and usually there are advanced warnings, like low oil pressure, high temps, rough running. The most common cause is fuel, not enough, wrong type, contamination, poor fuel system management, all factors that the pilot has complete control over.