Please include "Crashing Into Mountains" into the subject line. It's a bit clickbaity right now.
We updated the title again from “Eliminating the largest cause of death in jetliner accidents”. We're open to better alternatives.
Don Bateman’s terrain mapping device
11–20 of 28 posts
Re: Don Bateman’s terrain mapping device
#12Earlier quoted context omitted.
This reminds me of my sometimes curiosity into why helicopters don't have a central parachute, presumably located in the center of the main rotor. Not a parachute for occupants, mind you - for the entire helicopter. Why isn't that workable ?
Auto rotation provides a built in parachute when the helicopter loses power. Mechanically losing blades is like a wing falling off an aircraft and basically never happens. There are a few edge cases dealing with loss of control that are rare. https://en.wikipedia.org/wiki/Autorotation In combat helicopters ejection seats are just safer as 'helicopter on fire' is a real risk. Further, parachutes don't really work unle…
This might be a dumb question, but when an ejection seat is activated, what prevents the crew from being fired straight into the helicopter blades?
Re: Don Bateman’s terrain mapping device
#13Earlier quoted context omitted.
Auto rotation provides a built in parachute when the helicopter loses power. Mechanically losing blades is like a wing falling off an aircraft and basically never happens. There are a few edge cases dealing with loss of control that are rare. https://en.wikipedia.org/wiki/Autorotation In combat helicopters ejection seats are just safer as 'helicopter on fire' is a real risk. Further, parachutes don't really work unle…
This might be a dumb question, but when an ejection seat is activated, what prevents the crew from being fired straight into the helicopter blades?
They release the blades which fly off at high speeds.
Re: Don Bateman’s terrain mapping device
#14Earlier quoted context omitted.
I would think the best way to eliminate the largest cause of death (ferrying passengers) would be with a detachable cabin [1] but given that most accidents occur around take-off and landing, it wouldn't make much sense. http://www.independent.co.uk/life-style/gadgets-and-tech/new...
This reminds me of my sometimes curiosity into why helicopters don't have a central parachute, presumably located in the center of the main rotor. Not a parachute for occupants, mind you - for the entire helicopter. Why isn't that workable ?
Helicopters get all their lift from the rotor. So, either there's a huge amount of air being blown around, making parachute deployment impossible, or the helicopter has no lift and is free falling, which doesn't give enough time to deploy a parachute at the low altitudes helicopters generally operate at.
Small fixed wing general aviation aircraft are often equipped with ballistic parachute systems, however. It's just what you envisioned - a parachute with rocket-assisted deployment.
Re: Don Bateman’s terrain mapping device
#15Earlier quoted context omitted.
I would think the best way to eliminate the largest cause of death (ferrying passengers) would be with a detachable cabin [1] but given that most accidents occur around take-off and landing, it wouldn't make much sense. http://www.independent.co.uk/life-style/gadgets-and-tech/new...
This reminds me of my sometimes curiosity into why helicopters don't have a central parachute, presumably located in the center of the main rotor. Not a parachute for occupants, mind you - for the entire helicopter. Why isn't that workable ?
In the case of engine failure the rotor acts as a kind of parachute (autorotation). If the rotor itselfgets damaged, the whole helicopter would probably start spinning wildly, making a parachute useless.
Re: Don Bateman’s terrain mapping device
#16Earlier quoted context omitted.
I would think the best way to eliminate the largest cause of death (ferrying passengers) would be with a detachable cabin [1] but given that most accidents occur around take-off and landing, it wouldn't make much sense. http://www.independent.co.uk/life-style/gadgets-and-tech/new...
This reminds me of my sometimes curiosity into why helicopters don't have a central parachute, presumably located in the center of the main rotor. Not a parachute for occupants, mind you - for the entire helicopter. Why isn't that workable ?
Probably because Autorotation[0] works better than parachutes. Let it fall, and let the wind keep the rotors spinning, checking the fall speed just a bit to keep the rotor speed under control. Save up enough energy in the rotors to slow to a soft landing just before you hit the ground. You also keep a pretty good amount of directional control, can turn and go forward and backward a moderate amount as needed.
A parachute big enough to land the whole helicopter would be huge even when folded and stowed and pretty heavy. I don't think it's at all practical to store it in the main rotor. It would have to be on the body, but the rotors would be in the way of a deployment, so you'd need a way to detach them safely that doesn't also make them weaker and more failure-prone. The helicopter would also have to remain falling in a stable way in order to deploy a parachute, but the rotors that are designed to keep the helicopter under control are in the way of the deployment. Yeah, let's just stick to autorotation for failure recovery, all we need is one little freewheeling mechanism on the rotor drive shaft, and we can keep using all of the same hardware and controls designed to keep the helicopter in stable flight, instead of doing without and hoping for the best or adding the weight and aerodynamic complexity of backup systems.
Re: Don Bateman’s terrain mapping device
#17Terrain map. HITS (highway in the sky) based on current fuel, aircraft flight characteristics, weather.
On an iPad.
Re: Don Bateman’s terrain mapping device
#18>Bateman was always fascinated with airplane crashes. As an 8-year-old school boy in 1940 in Saskatoon, Canada, he and a friend sneaked out of class after two military planes collided and crashed nearby. As punishment, his teacher made him write a report on what happened. A much more appropriate punishment than detention.
As is the custom, I have to get excited when our small town gets mentioned in either the news or HN. I'm also now going to be doing some research about this accident; we don't have a military airfield in town, but my understanding is that there once was.
We additionally had a pile of small airstrips all over the province commissioned during the war which have now been abandoned. It still surprises me that we had these at all, given that uhhh Saskatchewan was quite a ways away from the front lines.
Re: Don Bateman’s terrain mapping device
#19>Bateman was always fascinated with airplane crashes. As an 8-year-old school boy in 1940 in Saskatoon, Canada, he and a friend sneaked out of class after two military planes collided and crashed nearby. As punishment, his teacher made him write a report on what happened. A much more appropriate punishment than detention.
As is the custom, I have to get excited when our small town gets mentioned in either the news or HN. I'm also now going to be doing some research about this accident; we don't have a military airfield in town, but my understanding is that there once was. We additionally had a pile of small airstrips all over the province commissioned during the war which have now been abandoned. It still surprises me that we had thes…
If you come across any information on the accident, please post it as a reply here, I'd like to see it. Thanks.
Re: Don Bateman’s terrain mapping device
#20Is it just me, or does the crashes data look really noisy? Yes, since 2001 the maxima are clearly lower, but in the period 1974-2001 I don't see a lot of difference with the period 1950-1974.