adouglas

GB.... Since according to your post you don't know anything about it, then obviously you didn't build it. So...what's your interest/involvement in it? Thanks....

Okay, that answers all of that...thanks! The big problem, of course, is NO PLANS. So...no templates, no way to build the airfoils...big bummerino. Hmmm...would it be possible to bypass that little problem with cores from Featherlite and a TERF CD????

Waiter, you're torturing us. What are you talking about? Is this your airplane, or something? Is this a joke? Is this a troll?

What this fails to take into account is the total amount of power required to run the infrastructure (you need to consume electricity to produce the hydrogen, plus electricity to pressurize or liquefy it, and possibly to refrigerate it... and there are inefficiencies in that process), but let's assume you can get enough electricity from thes sources to make it work...the big issue is the COST of doing it. Things would be rosy indeed if we could afford to implement all of this stuff. Just because it's possible doesn't make it a good idea when ALL factors are considered. There are wind farms in California that are falling into disrepair because they cost too much to run...they're simply not economically viable yet. This is misleading. Energy per kilogram is not the relevant measure. Energy per liter is. The energy density of hydrogen per liter is very, very low, regardless of its state (gas or liquid). This is the fundamental problem with using hydrogen as a fuel in the real world. To carry enough hydrogen in an airplane to fly any significant distance, you'd have to liquefy it. Which means that you'd have to carry a large, heavy refrigeration unit capable of outstanding performance that would most likely wipe out the payload of the airplane. Road vehicles using straight hydrogen fuel have concentrated on high pressure vessels carrying gaseous hydrogen, but the range of these vehicles is a small fraction of that possible with a gasoline-powered vehicle...because the hydrogen my have high energy density per KILOGRAM, but very, very low energy density PER LITER, especially in gaseous form. Liquid hydrogen is still much less dense than gasoline, so the energy density per liter is less. All you need for a gasoline vehicle is an uninsulated tank that holds the fuel at ambient temperature and pressure. And you can carry less fuel because of the greater energy density per liter. Note that the most practical fuel cell vehicles in development are those that extract their hydrogen from gasoline. One reason for this is the opressive requirements for storage of hydrogen fuel. The bigger reason is the infrastructure question. Oh, really, now. Don't be silly. NASA does not use fuel cells because they're more efficient. NASA doesn't give a fig about internal efficiency. They use fuel cells because the byproducts are useful (heat, water and electricity), not because they're inherently superior in any other way. When you can produce water as a byproduct of producing electricity, it's a win-win...you don't have to lift the water out of the earth's gravity well in the first place. In a space vehicle the critical concern is not energy efficiency, it's weight...and EVERYTHING that gets consumed (except solar radiation) needs to be carried. If the total weight of an electricity-producing system consisting of a gasoline-fueled internal combustion engine, a generator, fuel, oxygen to run the engine, water to make up for that not produced by fuel cells and all the associated tankage and plumbing were less than the total weight of a fuel cell system producing the same amount of electricity and providing an equivalent amount of water, then you'd better believe that NASA would be using it instead. NASA will try to use anything that gets the job done for the least weight, no matter what it is. Ever wonder why the manned vehicles don't use solar panels? Because when the TOTAL system is considered, the fuel cell solution makes more sense, even though it's less fuel-efficent (after all, a solar panel has infinite fuel efficency because there's no fuel, right?). Efficiency is only part of the equation, and hydrogen is not the be-all end-all. If you disagree, then go join NASA and ask them why the first stage of the Saturn V was fueled with kerosene instead of hydrogen.

That would depend entirely on what I believe is called the energy density of the system. A tank of gasoline (petrol) has a LOT of energy packed into a small amount of fuel...high energy density, therefore a lot of energy available to lift the aircraft without having to lift a lot of fuel (and associated components). The basic problem with electric propulsion for aircraft is that the energy density of the system simply is not great enough for actual flight. The exception is the high-altitude electric flying wing built by NASA, but it draws power from solar panels that cover the entire upper surface of the wing (IIRC the wing span is over 100 feet and the thing's payload is considerably less than the mass of a human...but I may be wrong about that). The example you cited of a fuel-cell powered laptop is not applicable and is a bit misleading, because you only cited weight and endurance, not size. Build a fuel cell with associated methanol tank the same size as a laptop battery and I seriously doubt it would run as long as current battery technology. Also, laptop batteries don't have to produce much current. Running a high-output electric motor is a whole different ball game.

For some reason the forum isn't letting me edit my message, so here's some more accurate info. The Moller silliness I was referring to is the Moller Skycar, not the Aircar. The specific model is the M400. It has left the ground (proven by photos/video on Moller's website), but has (as far as I can determine) done nothing more than hover a few feet off the ground. I stand by my assertion that machines like this are a giant load of horsehockey. Go buy one, fly it to my house and land it in my back yard. Then we'll talk.

This crock of nonsense is darned close to being a one of those perpetual motion machines. Look, this isn't that hard. It's all about thermodynamics, which summed up goes like this: You can't win the game. You can't break even, and you can't quit. Deal with it. Huge performance at very low fuel consumption isn't going to happen. Period. I dare anyone to PROVE me wrong. Show me one single example of a machine like this that has actually worked. Go ahead. I'll wait. You can do just about anything you want if you throw enough fuel at it. Numerous examples have been produced by the US Air Force. (USAF Law of Aerodynamics: Anything will fly, given enough thrust.) Every engine has a level of efficiency...that is, it takes the energy given to it in the form of fuel, converts a small part of that energy into motion, and wastes the rest as heat. I cannot quote specific numbers unless I put more effort into research than I'm willing to do here, but it's typically very low...way less than 20 percent efficiency. And that doesn't even count transmission losses (e.g., the loss incurred in heating the wire that connects one thing to another in a hybrid fossil fuel/electric system like this one). So you've got an internal combustion engine with its inherent inefficiency driving a generator of some sort with ITS inherent inefficiency, driving an electric motor with ITS inherent inefficiency, which in turn drives a fan with ITS inherent inefficiency. Much commotion, much heat, little useful work. I didn't bother diving very deep into the website, but it looks like the internal combustion powerplant is a small one. Maybe, what, 50 hp? Add up all those losses and I'd be utterly amazed if they get enough thrust at the fans with that absurd driveline to lift the airframe off the ground, much less a pilot. Didn't anyone bother to tell these people that if they hooked the internal combustion engine directly to the fan it would be more efficient and lighter to boot? This thing, to use one of my favorite expressions, is a load of dingo's kidneys. It's remarkably similar to the Moller Aircar, a similarly hare-brained idea that for some reason keeps on appearing on the cover of major magazines (generally either Popular Science or Popular Mechanics) well over a decade after the sexy fiberglass mockup was first constructed. And the idiotic claims are in keeping with the ludicrous design: 400 mph! Anyone can fly it, no pilot's license required! Land it in your driveway and park it in your garage!!!! Oh, PUH-LEEZE. I've seen my mother drive. It's scary. I shudder to think what might happen if a bunch of people like that start carving up the skies in such machines. The Moller Aircar is (or at least was) supposed to have EIGHT Wankel engines in it to lift four people. At least Paul Moller is a bit more realistic about the power requirements needed for VTOL flight than these bozos. What happens when one of those eight engines fails was never explained. It still has not flown. I'll bet a large part of my anatomy that it never will, at least not out of ground effect. Geez, Clive, I would have thought that one of my own clan would have better sense than to even give this thing the time of day. FORWARD! PS: The Scots (Douglas is a Scottish name, for those who don't know) have had a tremendous impact upon world history. Many think this is because there have been a lot of brilliant, inventive Scotsmen, and this may be true...but it's also because the one thing that Scotsmen do best is LEAVE SCOTLAND.

Anyone know if they're down for some reason? I've emailed them at fthrlite@pacific.net twice in the last month asking for information (general stuff...what they offer and how much it costs), and have gotten no reply. Thanks...

Factual error...my bad. BM is not Windows-based. I don't know where I got that idea from. The principle remains the same. Would you trust your hide to a computer with zero backup?

The following is presented as an opinionated rant. Your homework is to read, absorb, ruminate and present your own ideas. I invite respectful disagreement and well-reasoned discussion. Keep the knee-jerk responses under control, if you please. Though this rant mentions one particular manufacturer, it is NOT, repeat NOT, as in NOT, NO WAY, NO HOW intended as an attack upon that manufacturer. In fact, one of that manufacturer's products happens to be one of my favorites at the moment. So I AM NOT ATTACKING THAT MANUFACTUER, m'kay? They are only mentioned in order to get the reader to think critically about the topic. So DON'T GIVE ME GRIEF FOR MENTIONING THEM. Please. ======== As an instrument pilot who has flown real-deal ILS approaches down to minimums in the snow, in a single, I will NOT trust my tender pink butt to some gee-whiz non-certificated glass gadget in that situation without a stone-simple backup in place. I'll trust EFIS as far as I'll trust vacuum gyros, but no further. I've seen stuff from builders about going all-glass, with no "steam gauges" at all. Even if I never flew IFR, I'd never rely 100 percent on an EFIS. I don't care how "capable" the technology might be...I've seen what the deal is with my own eyes (meaning sitting in a cockpit in hard IMC only a few hundred feet off the ground and traveling at 100+ knots) and felt the pucker factor with my very own precious sphincter, and having the backup is worth every penny, no matter what the cost. When you are an instrument pilot, you will eventually have a telling experience: You will be looking at an instrument, mechanical or electronic, and realize that your very life depends on it functioning correctly. The more backups you have, the better. Don't forget that Blue Mountain bases its stuff on Windows. Has your computer ever locked up? How would you like that to happen in hard IMC? LOOK AT YOUR COMPUTER RIGHT NOW, AND DECIDE WHETHER YOU WOULD TRUST YOUR LIFE TO IT, RIGHT THIS SECOND. NO ARGUMENTS, NO PREVARICATION, NO JUSTIFICATION..... DECIDE !!!!NOW!!!! (In the interests of fair disclosure, I use a Mac with its UNIX-founded OS, and though it's never let me down I'm not at all sure I'd trust it to get me home no matter what.) I'm not slamming Blue Mountain here...as far as I'm concerned, all of them are the same for now, because I'm years away from choosing. When it comes to making the actual choice of which way to go, there will be more information available and I'll decide based on that information. In the hard, real world of instrument flight, capability is irrelevant. Reliability is everything. When you fly hard IFR, you are by definition trusting your life to technology. You need to decide, before you get in the cockpit, how far you're willing to go with that trust. I am only willing to go as far as replacing one major system (vacuum). So, for me, the minimum for-real IFR panel would include at least one EFIS, plus a traditional mechanical/static-based airspeed, altimeter, VSI and TC. (This is RV-7 builder Checkoway's panel, BTW....the moment I saw how he did his airplane, I knew I'd like the guy.) Should the EFIS go teats-up, it's exactly the same scenario as vacuum failure in a traditional airplane. This is something that's not pretty, but I've trained for it. A second EFIS (the dual Blue Mountain EFIS Lite G3 scenario) would be really, REALLY great...better than a certificated vacuum system for sure! However, for VFR-only flight, I'll gladly give up a bunch of that stuff. I don't need a VSI or TC to fly VFR. So to start with, just install an EFIS, airspeed and altimeter. Or in an extreme sense, go Piper Cub-simple and delete the EFIS. Plan for the full deal and install it later. You are invited to discuss, compare and contrast. There will be a quiz next Friday.

Has anyone tried using the plastic from Glad's new "Forceflex" trash bags for the plastic laminate bagging technique? It's very stretchy...which suggests to me that it might be really good for tight compound curves.