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.

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.

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.

Bullet Proof?

While chasing that philosopher's stone of general aviation, the "bullet proof" piston engine, I ran across this stimulating post on aircraft engine reliability.

Based on the data posted, I estimated the fleet-wide odds.  Over a 25 year period this is the rough-order-of-magnitude fraction of aircraft engines (including automobile engine conversions) that experienced catastrophic in-flight failure:

Lycoming:         1 in 1000
VW:                  1 in 120
Ford/Subaru:     1 in 30
Mazda:              2 out of 3
Chevy:              4 failures each

This is based on actual NTSB accident investigations back to 1985, compared to aircraft fleet sizes currently registered (as of 2009).

The truth is probably significantly worse for the Subaru/Mazda because there were very few flying before 15 years ago or so.  People have been flying behind Fords since the 1930s (Model A) and the VWs since the 1970s and maybe earlier.  Chevy enthusiasts have been trying to fly the "big block" engines but most have been using the Corvair.  I am disappointed the Mazda engines did so poorly here, because I had/have high hopes for the Wankel (rotary) engine.

The VW conversions actually come out looking pretty good.  The Aerovee slated for use in our Sonex probably does better than above because the data includes ALL Volkswagen derivatives.

The poor record of the Chevy conversions may be slightly overstated, but then again maybe not, because if the author's data is to be believed, apparently there are currently NONE registered (I cheated and divided by one).  The first thought that springs to mind is that they all must have crashed or scrapped!

As a postscript, I will add that the engines that I found most often mentioned as "bullet proof" are the Lycoming O-235 and O-360.  That's encouraging news for our Bearhawk, which sports the latter.

Bearhawk CD

Got a package from Russ Erb today.  Hopefully it's more than just the back issues of Trials & Tribulations.  Oops, I mean "Beartracks."

Bearhawk Discussion Group

While the Bearhawk might seem to be on the more experimental side of the experimental airplane spectrum, that's not always a bad thing.

Yahoo's aptly named Bearhawk support group is a great resource. I mean, where else can you find people telling you how to position your pitot tube, put skis on your plane, and land it? Yeah, I thought so. I've been getting the daily emails, but really need to delve into the old messages.

One of our concerns is the fact that we need to find out what revisions have been made between the time this plane was originally worked on, and now. The people in that group are really helpful and intelligent, which is what we'll need to have on our side in the coming months...

Torrance Fire Department

Should be satisified with our hangar's new fire extinguisher: 2A-10BC rated.  $30 at Lowe's.