AK Crash ELT Beacon Didn't Activate!/How Many Others Recently?

[RADIOMAN015]

I've been following the crash investigation regarding the float plane crash that killed former Senator Stevens and others.

The other day one of the national newscasts indicated that the NTSB was investigating why the ELT beacon didn't go off and thus rescuers were not advised of the exact location of the crash.   Apparently the aircraft was spotted after it crashed by another aircraft/helicopter that apparently voluntarily respond to a search for the aircraft when it didn't make it to a particular fishing camp.

There's no mention of CAP involvement in the search/rescue at all.

HOWEVER, CAP has been involved in other searches for crashed aircraft in the last three weeks.  It would be interesting to find out if any of these crashed aircraft were transmitting ELT signals?

RM

[RiverAux]

I've always been told that the ELTS rarely work in actually crashes.  Probably worked in less than half the missions I've been involved in with CAP.

[RADIOMAN015]

I've always been told that the ELTS rarely work in actually crashes.  Probably worked in less than half the missions I've been involved in with CAP.

What's interesting is the plane was in tact in that area, isn't there a way to manually turn on the beacon in the aircraft?   Maybe it's a good idea, especially for bush pilots (and others) to brief their passengers on where it can be manually turned on.

I agree with you on this one, we had a crash about 1 month ago at a small airport in the western part of the state (landed short of the runway in a corn field) and no ELT went off.  Apparently they used their cellphone to call for help (minor injuries pilot & pax).  Last week another aircraft went down in the north western area (both pilot & pax killed)  and I don't think there was an  ELT activation.  Both aircraft did not burn and the tail area did survive both crashes.
RM   

[lordmonar]

There are lots of reasons for why and ELT signal would not be heard.

1) failure of the automatic activation circuit.
2) Failure of the transmit path (antenna/cable damaged in crash)
3) Failure of the elt unit itself
4) Failure of the batteries (inproper installation, inspection, etc)
5) Antenna blocked by aircraft or terrain (plane laying on its back, blocked by trees/rocks, debris).

As an electronics professional I have seen comm equipment dropped from over 100 feet and continue working like a charm.....and I have seen equpment bumped by a buffer cleaning the floor knock out hundreds of phone lines for almsot no reason at all).

Once you put electronics into a crash situation......there is really no telling what is going to happen.  They try to design the equipment to surivive a crash....but it is a crash and thing will break.

[PHall]

I've always been told that the ELTS rarely work in actually crashes.  Probably worked in less than half the missions I've been involved in with CAP.

What's interesting is the plane was in tact in that area, isn't there a way to manually turn on the beacon in the aircraft?   Maybe it's a good idea, especially for bush pilots (and others) to brief their passengers on where it can be manually turned on.

I agree with you on this one, we had a crash about 1 month ago at a small airport in the western part of the state (landed short of the runway in a corn field) and no ELT went off.  Apparently they used their cellphone to call for help (minor injuries pilot & pax).  Last week another aircraft went down in the north western area (both pilot & pax killed)  and I don't think there was an  ELT activation.  Both aircraft did not burn and the tail area did survive both crashes.
RM

All ELT's have a manual activation switch. It's usually labeled "ARM - OFF - ON". The switch is normally left in the ARM position at all times.

From what I have read on this particular crash, there was no warning. The survivor being quoted said  they were flying one minute and had crashed into the mountainside the next.

And there are all kinds of reasons for an ELT to not activate in a crash.
Switch in the OFF position, ELT damaged in the crash, Antenna damaged in the crash, Dead battery, etc...

The NTSB is just starting their investigation, the final report will be out in 12 months or so.

[CommGeek]

I have been involved in 37 plane crashes with CAP and various other agencies.  only 2 had working ELT's after the crash

[lordmonar]

I have been involved in 37 plane crashes with CAP and various other agencies.  only 2 had working ELT's after the crash

Remind me not to fly with you!   

[RiverAux]

According to NASA, ELTs activate properly in only 12% of crashes.
http://searchandrescue.gsfc.nasa.gov/beacons/index.html

Not sure how old that data is and I'd be interested to see if there is enough data for the newest generation of ELTs to know if they are also that unreliable. 

[CommGeek]

No...not me in the plane crash...  HAHA

[coudano]

but it is a crash and thing will break.

Let's not forget burn also.

[SarDragon]

but it is a crash and thing will break.

Let's not forget burn also.

ELTs are pretty sturdy. I recovered one that had been rattled around pretty well in a Dumpster, and it was still sweeping away.

The burn issue is a big trade-off. The FAA recommends mounting the ELT as far aft as possible, to increase survivability, but it decreases accessibility for maintenance and deactivation. I've seen a couple of instances where the ELT burned up because it was too far forward by just a couple of feet. It wouldn't have made any difference for the occupants, but location of the crash would have been easier.

[coudano]

Not just the ELT itsself but also the antenna/mount, and the coax that runs from the elt to the external.

I've also found "free floating ELT's" ejected from the airplane during the crash, found pretty darned far away from the actual hull.  Of course the hull was spotted easily, but we had to DF down to the actual transmitting ELT brick in the bushes somewhere else...   eesh.

Nothing else like picking through bloody spilled luggage to get to the transmitting  ELT underneath.  /debrief


This is one of my biggest concerns about the 406 and its allmighty databurst.
Any disruption to the transmission system at all, and the impedence/attenuation on the signal is going to preclude the effectiveness of that 406 burst transmission.  Even if the 406 carrier makes it to the satellite, the data in it may be useless.  That includes the plane being parked inside a metal hanger, I beleive...  I haven't seen data on how that affects reception but I can imagine...  Now factor in burns, ejections, airplanes flipped upside down, submerged, in steep terrain, and so on.

but it is a crash and thing will break.

Let's not forget burn also.

ELTs are pretty sturdy. I recovered one that had been rattled around pretty well in a Dumpster, and it was still sweeping away.

The burn issue is a big trade-off. The FAA recommends mounting the ELT as far aft as possible, to increase survivability, but it decreases accessibility for maintenance and deactivation. I've seen a couple of instances where the ELT burned up because it was too far forward by just a couple of feet. It wouldn't have made any difference for the occupants, but location of the crash would have been easier.

[SABRE17]

speaking about accuracy, one actual ELT search involving a 406 i was on involved cordinates from AFRCC, they were almost two miles off and only made life a pain u know where, i definitally think there might be some issues to be worked out involving those things

[whatevah]

the last actual downed aircraft search I think Delaware Wing participated in was for a helicopter in NJ.  Once it was finally found, the switch for the ELT was in the "Off" position.  Wonderful.  Both occupants DOA due to severe g-forces on impact, but would have saved a lot of time and fuel.

Of course, it landed 100 yards off of a highway but in dense tree cover.  CAP flew over the area several times but a state police helicopter spotted it by looking through the hole left in the tree canopy when the bird crashed and spotted it.  Took a few passes before they saw it as well, since it kept going after it broke through the trees.  I was on a ground team from DE, I stayed at the scene overnight for security until the NTSB rep and salvage crew arrived.