AT LEAST half the time? Come on now. That just pegs you as a pessimist. If you had said 50/50, I could go along with it...
No, today is a very mild day. It's very unusual for there to be less that what we are seeing today so I am not being pessimistic. Just because it doesn't meet your expectations or proves to be a burden does not make it pessimistic.
But before you pull out random numbers, can we at least start to approach numbers that would be representative of what such an aircraft might actually look like?
Those are very middle of the road performance numbers for an aircraft of the size, power and configuration you are talking about. The reason I used "roughly" is simply because of the effects of winds, et cetera.
KR1... 80hp 180mph (spec'd to fly with 60hp, probably has a cruise around 150-160 with that power.)
Hummelbird... 32hp 115mph (that's almost 120mph with less than half the horsepower we are discussing)
Sonerai I... 60hp 150mph
BD-5B... name your engine, these things would cruise more than 120mph on 65hp
Wittman V-Witt 1600cc 150mph (I believe a 1600cc VW is about 65hp. Correct me if I'm wrong)
Sambada US-10 65hp 152mph
Quickie Q2 65hp 140mph
How many of those operate at high altitudes (and are thus equipped with heating, oxygen systems, seals on the doors etc) and how many of them have you set in?
I can tell you right now that a KR-1 or KR-2 is not a comfortable aircraft for anyone of average size (and I'm literally the 50th percentile adult American male in every aspect pertinent to cockpit layout). Ken Rand was a tiny little fellow (5'5" or so and about 160 lbs from what I have been told) and designed his aircraft to fit himself. Trying to design to fit someone who is taller, broader and heavier is going to require a larger cockpit and therefore more drag. As well as the need to account for the weight of an average adult American (200 lbs or so) which will require a larger wing if you want a decent amount of baggage. Then if you want to bring along a friend (which most of us do)....
The Sonerai I has a 300 statute mile range so it's not exactly a "cross-country airplane". I've flown one. They are a fun plane...actually they are a ****ing blast to fly. However, it doesn't meet most people's idea of a cross-country plane.
As for the Hummelbird, that's definitely not a plane you want to spend a lot of time in. It's like wearing a sweater designed for a child.
File:Skeet Wyman Hummelbird.JPG - Wikipedia, the free encyclopedia Take a look at one compared to some adults and you'll see what I mean.
The Bede design...well, if you think you're that talented of a designer....I mean between Jim Bede and Burt Rutan that aircraft has one hell of a pedigree.
The Quickie is a heck of a design but it's severely lacking in range (about 500 miles) and, once again, look at who designed it. Mr. Rutan is a bit better versed in aircraft design than most.
The Sambada? Never heard of it.
150mph cruise seems completely attainable, based on the several examples I listed above. I'm just trying to understand here.
150 mph at say 8,000 feet is one thing if you're willing to sacrifice comfort, range and- to a large degree- safety if something were to go wrong. 150 mph at 18,000 is entirely another simply because of the requirements to protect occupants from the environment.
-20 C temperatures are not to be trifled with. Human skin freezes very quickly at temperatures around that (
Proc. Am. Phil. Soc. 89: 177–199, 1945 if you want to fact check) and that's even without the help of a 150 mph slipstream. Lose a window or something and you're instantly blinded by the wind. There are a lot more factors at work here than just "Can you build an airplane that will go fast at X ft?"
As best I can tell, the biggest issue is the inability to use Constant Speed props, but nobody here has yet had the brilliant analytical mind to bring that matter up.
The biggest reason they aren't normally used on small aircraft (those just above the weight limit of the LSA category) is a simple one: weight. If you are trying to achieve the goals you've set for yourself, you're going to have to keep the weight down.
Why? It adds complexity and weight to a category of aircraft that are meant simply to be for the "fun" of flying. That said, I suspect that the primary reason behind the entire sport pilot movement was a thinly veiled attempt (in the safest way possible: light slow aircraft with as few people on board as you can get by with) at proving or disproving the ability of pilots to medically self-certify.
I'm referencing a single seat design,
Noted. You might be able to pull off the performance you want in terms of speed but I continue to staunchly argue against the altitude concept. That said, if you simply want to go fast and there are planes that accomplish that in the category you're looking at, why go through the trouble of designing your own? It's a much bigger headache than you likely imagine.
but not LSA restrictions. I thought that would have been clear by my initial posts and also the international nature of this forum. My apologies
However you want to look at or try to justify it- other than speed- you're talking about an LSA for all intents and purposes.
It's hard to justify a pilots license when I can get 40mpg on a motorcycle that goes 0-60 in less than 3 seconds.
Which has what to do with the discussion at hand?
But I do have my A&P and considerable composites manufacturing experience
...and? You speak like someone who has no background whatsoever so it was an educated guess that you're a rank newbie to the world of aviation. What was I supposed to suspect about someone who acts as though they don't an aileron from their asshole?
for you to turn your nose up at, if you'd like.
I probably have as much experience with regards to aviation safety, human factors, crash survivability and related topics as anyone on this forum (since it's what I do for a living) so if you want to stop turning your nose up at my area of expertise. You have just gotten your tail in a knot over the fact that a couple of us have pointed out that your goal of having your cake and eating it too is not likely to happen and even if it does, you will be very likely to end up getting yourself hurt with the attitude that "I can overcome that!" that you've demonstrated on this thread. No offense intended but if others haven't done it before and it's not a common practice there's probably at least a few dead people (or at least a lot of failed designs) to explain it.
Towards that end, I'll leave you with a quote from Douglas Adams: "Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so." That disinclination is exactly what I'm seeing in you and I have seen in before in another friend of mine. His name was Daniel Lloyd and I'd suggest that you two have a long talk but unfortunately, when his hubris finally caught up with him they identified Daniel by his dental records and fingerprints. I don't take saying that lightly nor do I wish to quash the desire to move the world of aviation forward but you asked what the challenges where and I have gone over a lot of them for you. You can take that as either my being a dick or you can look at them and use them to improve your goals and the design that is trying to meet them.