UL runs out of gas, caught on video.

[FN FAL]

Y'all don't know what you're missing! Most UL's are very high quality, and plenty safe. You really should try them!

You know what, your post inspired me. I have been stopping by a really cool hang gliding club for many years to just watch them take students up and enjoy the afternoon. I may just have to pony up the bucks and let them teach me something new before I get too old to try it.

I think it would be a hoot.

UL Relevance: They use ultralights to tow the hang gliders up. It's always fun to watch those guys fly.

 

[mtrv]

avbugs advice makes sense to me. When I had an engine failure in a 172 I put it into a tree line in a small field. didnt stall but tried to dissipate as much vertical speed as possible.. I came out fine, my student had a cut on his leg. The seatbelts did their job.

In the case of the Cessna 310, the last second stall wasn't on purpose, yet it saved their lives. The pilot thought he was decending through some scattered clouds to an unsheduled fuel stop due to high winds, but quickly noticed it was a mountain with a 45 degree slope, and he was about 300' below the peak. He firewalled both throttles, and pulled nearly full back, just as the aircraft was going to slam into the upsloping terrain. The stall horn blasted, and the aircraft's belly instantly became a near 45 degree match to that of the terrain. With so much airspeed disappated, it merely caught a wing, and flipped over. Yet it had no massively crushed airframe, and looked like a complete airplane sitting on the mountainside.

In this case, when you're looking at rising terrain filling the windscreen, then pulling back is the only possible option, stall or no stall. Better yet, get a new Garmin or other GPS device with moving map terrain features.

 

[Metro752]

so wheres the injury list

 

[BushwickBill]

Anyone know offhand the glide ratio of the type of UL or similar?

 

[avbug]

You say to maintain a speed of approximately Vx, all the way down to impact. Obviously this is considerably higher than stall speed. While it's true that you can typically survive greater horizontal forces than vertical, you forgot a minor detail. Just because an aircraft is stalled, doesn't mean there isn't any forward movement through the air. When we land a light single, we typically touch down very very close to stall. But there is still about 45KIAS or so as we touch the runway. If you pretend the tree-tops are a runway, you wont be dropping it in and subjecting yourself to these deadly vertical forces, as you claim. Even if you stall, there is still forward movement.

The trouble with your system, is that you hit with much greater forward speed. If you hit a thick enough tree, the rapid deceleration is going to kill you in a heartbeat. Whereas if you had simply stalled just above the trees, you forward speed will be much slower. Think about it. You have to fall through these trees no matter what you do. Better to hit at the slowest possible forward speed. This will minimize deceleration forces that can kill you.

Bad, bad, bad, bad, bad advice, and certainly not borne of experience. Sounds good on paper. If you don't think about it too much.

Certainly forward impact isn't good for you, but you can take a whole lot more forward impact than vertical impact, by a long, long shot. Your aircraft is a whole lot more capable of absorbing forward impact than vertical impact.

"Deceleration" forces are really acceleration forces, being a change in speed or direction, often both. Vertical acceleration is a far more critical issue, particularly with respect to survivability and potential for injury, than forward acceleration, by orders of magnitude.

Have you spent a great deal of time skimming the treetops or landing on water, and have you made forced landings and intentional landings in rough or hostile terrain? I certainly have, for a living, and I often face the prospect of entering the trees, or arriving at the rocks or the side of a hill second-by-second during any given flight. It's not academic to me, and I've known enough folks who tried it both ways, myself included, who can tell you first hand what works and what doesn't...and I know enough folks who can't tell you what doesn't because they're no longer here, to assure you that you're talking garbage. You think you know what you're talking about, but you really don't...and probably won't until you try that stunt one day and you either get lucky and learn, or it kills you.

Good luck with that.

 

[Lead Sled]

I’ve had my share of experience in ultralights. One of my best friends has been involved in the manufacture and design of several commercially successful models over the past 30 years and is one of the few remaining in the business today.

Are they safe? Most of them have 2-cycle engines that can be pretty temperamental. Additionally, many of the are design on the “looksa” principle as in “that looksa 'bout right.” You are also going to be using new technology in many cases - several years ago in an ultra-light (my last UL flight, by the way) the composite propeller shed a blade and the resulting vibration ripped the engine from the mounts. The UL had amphibious floats. I was flying a 400' pattern and had no choice but to go into the corn field I was flying over which was adjacent to the pond that we were flying off of. The float braces got tangled up with the corn stalks as I was flaring to land. It rolled the whole thing up in a big ball – the ultralight, me and a bunch of corn. I wasn't hurt, but like I said it was my last UL flight. Would I fly one again? Good question. Designs and the quality of materials have improved since my episode 18 years ago. I've seen a couple of new sailplane and amphibious designs that could be very tempting, but only with a ballistic parachute.

Are they fun? I was having a blast up until the point I had to start picking the corn out of my teeth. The one that I flew the most handled just about like the old 65hp Aeronca 7AC Champ that I learned to fly in. The highest that I’ve ever been in one is over 13,000’ – working a ridge, just like I used to do in my gliders.

Are they cheap to fly? A gallon or two of car gas and some 2-cycle oil is about it. They are not "aircraft" as per the FAA so all of the maintenance, airframe and engine, is completely up to you. They can be pretty spendy to buy. Like everything else, you'll have a pile of money tied up in one by the time you're through. There's probably not a lot of difference between a spiffy new ultralight with all of the "whistles and bells" (and don't forget the ballistic chute) and what you'd have to pay for an older 2-seat trainer. I would think that the main difference would be in operating costs.

For you guys trying to build time, there is also another consideration. A part 103 legal ultralight isn't an aircraft, no pilot ratings are required to operate it, no flight time that is accrueable towards any FAA certificate can be obtained in one. However, they can be built and certified as experimental aircraft and then the time is would be logable.

FWIW, here are my thoughts on the proper speed to crash…

Generally, you will want to impact as slowly as possible; but you will also want to maintain enough speed to insure that you have control. Remember, if you double the stall speed, you multiply the kinetic energy four times. The survivability of a crash is a function of how quickly the kinetic energy is dissipated. If given the choice, you'll also want the airframe to absorb as much energy as possible; that way your sweet fanny will have less to deal with. If you’re lucky you’ll have a flat smooth surface, but throw in some rocks, trees, etc. and you quickly see why survivability can be a big question.

‘Sled