Tuesday, March 23, 2010

False Alarm

Well, our ELT works.

I stepped out of the hangar and saw a guy in a city vehicle headed my way.  Uh oh.  Did a lightning-fast hangar scan for combustibles, etc.  If there were any I would have thrown them in the trunk of my car.

He rolled up next to me and asked how long I had been here today.  Since about 2:30 PM.  I looked at his conspicuously displayed antenna and he explained that he was trying to track down the source of a 121.5 MHz emergency beacon.  Probably somebody's airplane's emergency locater transmitter (ELT) had gone off accidentally.  Meaning with NO accident.

I volunteered to check my ELT.  I knew we have one for the Bearhawk, but I was relieved when I was actually able to run into the hangar and find the big orange ELT in the first cardboard box I laid my hands on.



I walked outside and cycled on my ELT, heard the warble of the DF equipment in his truck, and turned it off again, demonstrating that our hangar was not the source of the distress signal.  He thanked me and rolled on.

Afterward, I looked it over, and the date of manufacture was February 1975.  Battery had probably not been checked in several years.  It worked anyway.



Later I saw the city guy parked outside a hangar down the row on the other side.  I gave him the long distance thumbs up/down question, and he shouted the update to me: he had found the hangar that seemed be be the source of the radio beacon, and called the culprit at home.

As I left for dinner, it was my turn to roll by and interrogate him.  The U.S. Air Force Rescue Coordination Center was calling him from Langley (Virginia) every 10 minutes to find out if he'd found the beacon yet.  The dude whose hangar it was still hadn't shown.  "Yeah, he lives right nearby and he said he'd be right over, but it's been 40 minutes."

Nuisance ELT transmissions on emergency channel 121.5 are one of the reasons for the change over to the new, 406 MHz GPS-linked ELT standard.  For now, I can legally put this old one we already have in the Bearhawk (with a new battery of course), and it would probably start transmitting if I crash land, but there's a good chance that help would never arrive due to incidents just like this one masking my signal.  Oh, and 121.5 will no longer be monitored by satellite, so we'd be at the mercy of ground stations and passing aircraft that might be monitoring 121.5 or 243 MHz.  I know I don't do that often when I am out flying.  Much more likely to be on Flight Following or Flightwatch, or just the next frequency on my flight plan.

Yeah, maybe we should spend the money (~$1k) and get a new 406 MHz ELT, synched to our GPS.  Besides our precise position, data transmitted to "Langley" would include aircraft type, registration, and home phone numbers.

Friday, March 12, 2010

Bearhawk Crash Update


Thanks to the Bearhawk mailing list, I found out about an update to the only fatal accident involving the Bearhawk. The accident happened last year, and resulted in all three on board dying. Tests are starting to point to carburetor icing as the cause.

What is also interesting to me is that there is actual video from onboard the airplane. This is an excerpt from the report:

"The camcorder was largely destroyed by the accident; however, the tape (8mm video cassette) received only minor damage and was also sent to the Board's vehicle recorder for review..."

There are some interesting observations about the sounds they hear, and whether or not it came from the engine or the movement of the actual camera. It would be great if the NTSB had easy public access to this kind of evidence, and I'm considering filing an FOIA request for a copy when the investigation is concluded.

I'll post an update when the final report comes out, which should be in May of this year.

Monday, March 8, 2010

Unmanned Aircraft Systems


There was an article in one of the latest Aviation Week magazines about the British Mantis UAS (or UAV depending on who you are). It was amazing how fast it went from concept to development, and it seems that could potentially apply to experimental airplane design. That there are so many interesting designs for these craft, and several of them have the ability to stay aloft for long periods of time.