Jim,

I’ll re-affirm what Gary said about Experimental. We made the upgrades and did local test flying anyone would deem appropriate for whatever upgrade occurred. I.e. lots of approaches with the new a/p. O2 testing at altitudes where we still had good cabin pressurization. We can hold 12,000 foot cabin to FL240 or so. Log entry and then be smart about it. Handle it responsibly as if your life depended on it.

When we put in the new engine, we put the plane back into Phase 1 test for 5 hours and complied with all appropriate requirements specified in our operating limits.

Other than that, it was just logbook entries.

With Experimental (Exhibition) you can really do almost anything you want. The only question is whether you have to go back into Phase 1 for a period of time. That is typically required when you make a major alteration to the airframe that could effect performance and/or handling OR if you change the nature of the power plant.

As an aside, we also have one of the few T-6 Texans that is Experimental-Exhibition. We wanted to put a good a/p in it because we fly about 50 hours a year of long cross country in it going to/from airshows, formation clinics, and whatnot. The only autopilots that are approved in the normal category Texan are archaic pieces of … stuff. But, we’re Experimental so we can put in whatever we want with no fuss. So we put in a Garmin a/p that does everything beautifully. Log entry. Local test flying to tune it and make ourselves confident it works as intended. But, no approval by the FSDO required. No 337. So STC. Log entry.

Zeke

Zeke/Gary -

Do these L-39s have 'hot' ejection seats in the aircraft?

in my research, seems about 25% of the fleet has hot seats. It's some old russian design (I don't know what seat is in it).

The survivability after ejection seems to be low; in the few high-speed aborts I've read about (including the one on this thread that was at PVG), the pilot seems to do better in the aircraft compared to leaving it.

I actually looked at the airframe that went off the end at PVG, it was surprisingly robust and did well in spite of going through the trees. the cockpit was completely intact.

in addition to the inspections, I understand it's very difficult to get pyro that isn't expired.

I'm going to leave my seats cold.

Seems to match what I found out between asking my question and reading your post.

ATAC's fleet have hot seats. Guess the one in Santa Fe that my friend took his checkride in was cold seat. He also mentioned the trouble of getting the pyro for the seats from Czech Republic. I asked about MB seat mods during rework. His response was that it might be available but probably fell into the too hard category. Yes - I know it would be VERY expensive to maintain any seats.

Brian,

Our research when we were buying indicated that hot seats didn’t make sense because of:
Cost to maintain
They don’t actually save lives in US operation. (See next paragraph)
I’m too big and out of limits for the seat
I don’t want to give rides to people who aren’t WELL experienced in hot seats. Risk greater than reward. And I like to give rides.

When buying, our research showed there had been 5 attempted ejections in the US civilian market and no survivors. Most, if not all, of those five pilots were ex-US military aviators and should have been as well prepared as one could expect in the civilian market. I.e. they had prior experience flying aircraft with hot seats. And they all tried and failed. My recollection is that most were outside of envelop when they pulled. If they couldn’t make it, what chance did I have?

Zeke

I understand everything you say Zeke - but I never gave much credence to ejection seat envelopes.
It wasn't like I was going to sit in the jet and say - well I'm 30 kts too fast or 300' to low in the dive or any other parameters. I was pulling the handle. I'll take my chances with the parameters rather than a fireball.
Being to big for the seat is a concern...in the Hawker Hunters I flew for ATAC I had to have 60 kts on the jet for a ground level ejection IIRC. It was my first time in a non-0/0 seat. Strange concept for me - but again - I'd take my chances.
I'm curious more about 5 ejection attempts ALL outside of the envelope and what were the flight parameters of this mishaps. Do you have other details?

Brian,

I agree with you - if impact is imminent, I would pull and roll the dice. That said, it didn’t work for these guys. And they had better prior experience than I did.

I don’t recall the specifics. It was four years ago when I got the information, I made the decision, and then the specifics were dumped from my brain - for better or worse. I only have two good neurons and I have to save them for what’s ahead of me.

Also, the rest of the reasons remain valid.

A friend owned a civilian PC-7 and PC-9. The -9 has hot seats. He sold the 9 because he likes to fly with friends and he won’t take non-qualified people in a hot-seat aircraft. He also has an L-39 will cold seats.

Z.

We've got two L39's here at Pompano Beach Airpark, Jet A at $5.62, and closer to $4.50 just a few airports away. Maybe a winter get away is in order? There are several more L39's and they get together often for formation flying and even local airshow demonstrations. There's nothing quite like watching two L39's in the overhead break circling to land while the Goodyear Blimp is also in the pattern.

One successful ejection was in Europe by Breitling in 2012, apparently they lost an engine and ejected at 1500-2000 feet. Here's the link: http://www.aero-news.net/index.cfm?do=m ... fcdfbfa2d3

But I agree the statistics aren't on your side. I have cold seats in mine.

Zeke-

I found this thread. still flying your L39? Who else on BT has one?

in my research, seems about 25% of the fleet has hot seats. It's some old russian design (I don't know what seat is in it).

The survivability after ejection seems to be low; in the few high-speed aborts I've read about (including the one on this thread that was at PVG), the pilot seems to do better in the aircraft compared to leaving it.

I actually looked at the airframe that went off the end at PVG, it was surprisingly robust and did well in spite of going through the trees. the cockpit was completely intact.

in addition to the inspections, I understand it's very difficult to get pyro that isn't expired.

I'm going to leave my seats cold.

I’m looking for the Maint manuals on the airframe/systems.
Found the engine Maint manuals. Hopefully I won’t need and engine for a while. This one was OH’d in 2016 and has 200 hrs.

BT's own Matt Guthmiller also recently acquired an L-39. Videos on his Youtube channel...

I get the point of hot seats being problematic, but how well does the L-39 do with an off-field landing? I could see maybe doing a manual bailout at altitude, but lose the fan right after takeoff and you're riding that thing in.

You mean this one?

There is research showing unsuccessful ejections (most likely outside of the envelope), but are there instances of any successful off airport landings? Or of any jets of this type?