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Wow, anyone paying attention to Reno this year? While the unlimiteds are great, I really enjoy seeing what the sport class is doing. It is interesting to me that it has not been the same type aircraft winning year after year. Lancairs, NXT, and now Jeff Lavelle and his amazing Glasair III. Almost 400mph and it's a design from the mid 1980's. What a plane!
That's incredible! I had no idea you could make a Glasair go that fast! Kudos for Jeff Lavelle on this amazing accomplishment.
Attachment 2440
I wonder what factory VNE is for a Glassair, and if there is danger if they are exceeding that.?What engine is he using, I'd guess that it is turbocharged?
And T-6 winning speed was up to 243, which is about 100 mph over normal economy cruise! Must be really noisy at the speed!
I got curious and looked up the specs on VNE for the III and it is given as 335 mph, so he is way over that by 60 mph, and again I wonder how safe that is. It's hard to telll by the one photo by the pylon but looks like he might have shorter wings also.
By contrast stock P-51 VNE is, I think, about .8 Mach so Strega, even at 525 or so on the straights would still have a good safety margin and of courese with shorter wings is heavily modified.
Vne on the III is 291 knots in the manufacturer specs.
The source that I got on google gave the speed in mph. Normal top speed is 300 mph at 18,000 feet, and vne of 335 mph. If you multiply 291 knots by 1.1512 you get speed in mph which at 335 is the same thing, and almost 400 is still way over vne.
Well it is 335 mph Indicated (well, probably calibrated). Converting to true air speed is about 370 MPH at 5000' and some reasonable temperature and pressure. So you only have to perform an analysis of what you need to bump the limit up by 30 mph.
This vne conversation is a little odd given that virtually all race planes race beyond their original vne. The smart racers carefully test their airplanes incrementally beyond vne. With regard to the glasair 3, the structure is one of the lessor worries even at those speeds.
There are many things that go in to Vne. Some of them aren't going to be a problem. I can almost guarantee the III used is substantially lighter than the spec gross weight for instance.
I was there Thurs-Sun, and the Sport Class was my favorite class to watch! Those guys were having a blast...and that Glasair III was just HOT!!
Todd, I wouldn't take VNE too lightly no matter what airplane.
The Glasair is not immune to control surface flutter anymore than any other airplane.
If he is flying faster than VNE, which I think he probably is, there is that risk.
I don't have all info on VNE, and don't have time to research it right now; But one source says that manufactures leave a 10 % margin above started VNE for safety, also that VNE is based on true, not indicated airspeed.
I agree that vne is a very important number in an airplane. I will certainly always respect it when I fly. My point is that these guys are flying at high speed at 100 feet off the deck turning left, pulling g's and flying very close to each other and at power settings that could cause an engine failure at any second. VNE probably isn't their biggest concern while racing given it is the intent to go that fast in the first place. I would also suggest that these pilots have taken their aircraft to these speeds many times previously to test the airframe for flutter and any other concerns regarding the speed involved.
There is technically no "glassiair Vne". There's a number the factory puts in their spec, but these things are individually certified experimentals, so it is whatever the builder who takes it through certification sets as a number and convinces the DAR or FAA guy who signs it off to agree to.
Your last statements are all wrong, Bill. There's no requirement (nor necessarily practice) to leave any headroom over Vne. Part of that myth is that Vne can't be more than 90% of certain design speeds used in certification, but that doesn't mean that you've got headroom there.
Vne is calibrated (closer to indicated) not TRUE. This is why I made the point earlier. Saying he has a 400 mph aircraft (true) aircraft is a lot closer to the 335 Vne than it appears.
Presumably they worked up to those speeds progressively to test for flutter. Other factors such as loading issues in Vne are also testable and as I stated, probably less of an issue because the plane is being flown at much lighter weights than the gross weight that the factory number is based upon.
Ron, I have not gotten what I consider the final info on VNE yet. B
If you go on Google and put in VNE speed, you get a number of sources including Vans A F, and one called "Tailspin Tails". On there it says the VNE is based on true not indicated airspeed, that VNE is slower at higher altitudes and that the designer sets VNE at 90% of max design speed ( thus the 10% margin that I referred to).
Nowhere does it confirm that VNE is set at full gross like stall speeds are.
VNE is to protect the plane against it's "aerolasticity" or flexing of the airframe that may lead to flutter and airframe failure.
Todd, I would bet that some, if not most Reno race planes, especially the larger ones, in fact did not go out and dive to max speed before the race. They are not going to risk running their engines that hard until it is race time.
There is now some thought that planes ought to be tested as such before the race, but I am not sure if that is a requirement yet.
In the past I know some planes aren't even ready until race time and may not even have the race engine in until at Reno.
Finally, Ron just because it is a homebuilt I am not so sure you can legally ignore any designer specs. Let's say that iinstead of a Glasair you call it a Moe, Larry and Curley special. Can you legally fly it 500 lbs over factory set gross weight?
And I doubt if an FAA inspector or DAR is going to sign off on some speed or weight or othere parameter that is above factory specs anyway.
An air race may be different and have some sort of waiver, just as one can get a waiver to ferry overgross planes across the ocean.
I am sure that none of the racers at Reno take VNE lightly. Second-guessing the experts might be fun, but is usually not productive. No harm in speculating on a discussion group, but I doubt anyone here knows what he did to accomplish that (100% mass balancing control surfaces, careful testing, etc.)
That is not a stock Glasair by a long shot, and the owner is no idiot. The thing produces 750 HP! It is obviously capable of exceeding the kit manufacturers listed VNE, while pulling something like 3 to 4 G's doing it.
Riley, what kind of engine does it have and how do you know it produces 750 hp?
It might have 750,but I don't know any standard production piston Lyc or Con that has that much. Maybe it is an auto engine.
I don't know about the sport class, but can tell you that the T6's are not running above VNE on the indicated airspeed nor are the G's anywhere near what the aircraft are certified to. We do get close to the VNE on the downhill during the start.
Yes you can, and it is done legally. As a homebuilt builder, you are the factory.Quote:
Originally Posted by Bill Greenwood
As I said, I believe your assumption on the 10% is WRONG. The Vne in part 23 is determined by the lowest of a half a dozen factors. Some of those are set to .9 of certain other design speeds, some are not.
It is not guaranteed that you have 10% headroom.
Vne is by definition calibrated airspeed and for MOST of the factors that are limiting, true airspeed is immaterial. Now however, there are other issues. The principle you're talking about is probably best described in this article: http://www.vansaircraft.com/pdf/hp_limts.pdf While it does show that flutter issues may arise based on true airspeed, but Vne is expressed as calibrated. It just may be that you have to set your calibrated airspeed based on the possible allowable true airspeeds and flutter characturistics. It is erroneous (as the postscript to the article shows) to just assume Vne as specified in indicated, is just a true airspeed number for the limit. If you do this, you'll be safe (because true airspeed is higher almost always), but you'll also be cutting off a lot of your envelope.
Twin turbo io580 lycoming. NOT an auto conversion.
http://mukilteobeacon.villagesoup.co...r-races/902273
Jeff LaVelle, of Mukilteo, won first place in the Sport Class gold 2012 Reno Air Races on Sept. 16 in Nevada, flying this experimental kit-built Glasair III.
The fastest Glasair airplane in the world is right here in Mukilteo.
Jeff LaVelle, of Mukilteo, won gold in the Sport Class on Sept. 16 in the 2012 Reno National Championship Air Races with his Glasair III, known as Race 39.
His Glasair dominated the class: LaVelle’s aircraft was the fastest type, fastest qualifier; he won every heat race, and then won the championship race on Sunday. His fastest speed was 393.552 mph.
While LaVelle did not officially record speeds over 400 mph, he was unofficially clocked at 403 mph during his final gold race.
“My airplane was flawless,” LaVelle said. “You couldn’t have asked for a better finish.”
“Glasairs typically aren’t that fast,” he added. “Certainly, mine is real fast. Now I’m the fastest. Period.”
Race 39 was so fast that LaVelle was lapping other gold heat racers on the 8.08-mile course by lap five. He finished well ahead of John Parker with his Thunder Mustang, last year’s winner. In second place, Parker’s fastest lap was 377.033 mph.
LaVelle is about 10 mph away from beating the championship race record of 407.061 mph held by Jon Sharp with his NemisisNXT. With it, Sharp won a record 15th Reno National Championship in 2009. He has retired from pylon racing.
But LaVelle’s goal isn’t to break Sharp’s record – not yet. LaVelle wants to keep winning Sport Class until he’s sick of it. Though, he doesn’t think he’d ever get sick of winning.
“What I really want is to win it for a while so there’s no doubt I’m the fastest, I’m the best,” he said. “And if I get bored with winning, and I want to blow the thing up trying to set a record, OK great.”
Started in 1964, the Reno Air Races are the last event of its kind. Held every September in the Nevada desert, the races have become an institution for Reno and for aviation enthusiasts from around the world.
The event features six racing classes, an air show and a static aircraft display.
The Sport Class highlights the innovative work being done in the development of high-performance kit-built aircraft. Sport Class airplanes race at speeds of about 350 mph or more.
His friend Todd Rudberg, also a pilot, was there in Reno to watch him race. Rudberg clocked his first lap at 399.560 mph.
“There is something so cool about seeing a little Glasair make a 400 mph pass,” Rudberg said. “You never see anything but the belly of the bird because he is turning throughout the 8.08-mile path.”
Let’s put the Glasair’s 400 mph into perspective: LaVelle would lap all of the planes in the Unlimited Class bronze heat. He would contest the win in the Unlimited silver and probably win it.
Both of those heats are full of P-51 Mustangs, F-8F Bearcats and Hawker Sea Fury. Fast airplanes.
However, the Unlimited gold airplanes are faster, with speeds up to 500 mph, so LaVelle has some work to do to put them in his wake.
LaVelle has been flying airplanes for about 20 years, racing them for six. He raced motorcycles for more than 10 years before that.
“I’ve always liked gas engine toys, mechanical things,” he said. “I always liked airplanes, even when I was a little kid.”
He bought the kit for his Glasair in 1998; about 18 months later it was built, and he was flying it. Without modifications, its fastest speed was 270 mph.
With the help of his crew, the Glasair has been highly modified over the years. It now sports turbochargers, a bigger engine, more horsepower, a different propeller and several aerodynamic improvements. They make refinements every year, and in 2012 it paid off.
“We try to improve it,” LaVelle said. “I’ve got another engine for next year that I think is going to be even faster.”
LaVelle’s first Reno Air Race was in 2007. He wasn’t as fast as he is now, but he still won Rookie of the Year.
His second year, LaVelle showed up with turbochargers. He passed his way to the front during the championships – and was about to win it – but his engine malfunctioned, and he had to call a mayday emergency. He didn’t finish the race.
In 2009, he returned with a better engine. He won every heat race in his class, and it looked like he would also win the championship. But 2009 wasn’t his year, either. LaVelle was disqualified for flying too low.
“I was devastated, because I had it in the bag,” LaVelle said. “I should have had it this year and the year before.”
Finally, in 2010, LaVelle won his first championship race. With his win, he also set a new record: 362.481 mph in the Sport Class.
In 2011, an airplane crashed into the stands, killing the pilot and 10 spectators on the ground, and injuring 69 others. The races were cancelled.
This wasn’t the first air race disaster in Reno. Three pilots were killed before LaVelle’s very first heat race.
“Pilots die all the time,” LaVelle said. “Before my race, I’m like, ‘What am I trying to prove here?!’
“As soon as you start the engine, then it goes away, and you’re ready to go.”
Because air racing is so dangerous, LaVelle has difficulty sleeping, eating – doing anything before a race. He’s all hyped up. Stressed with the anticipation of it. He can’t stop his brain from, well, racing.
“The waiting game is awful,” he said. “I hate it. I really hate it. The waiting, oh my god, it’s just nerve wracking.”
LaVelle is the owner and president of JL Manufacturing, an industry leader in aerospace manufacturing. He founded the company, located in Everett, in 1989.
When he isn’t pylon racing, LaVelle is flying his RV-4. He is also a pilot for the Blackjack Squadron, which flies RV kit-built airplanes in formation for the Mukilteo Lighthouse Festival, Arlington Fly-In and Airshow, General Aviation Day at Paine Field and more.
Rudberg is the lead pilot of the Blackjack Squadron, and he and LaVelle are the only two pilots in the group who fly from Paine Field. They’ve been flying formation together since 2008, and practice together several times a week.
Rudberg said he gets anxious watching his friend race – in racing, anything could go wrong – but that overall it’s just super exciting to see him zoom past overhead.
“Mostly I’m just excited to get his lap times, track his speed,” Rudberg said.
“When he’s dominating like that, like he did this year and in 2010, it’s exciting. You just want to yell, ‘Woo-hoo! There he goes!’”