Osprey Struts Its Stuff at Farnborough

In case Bruce hasn't posted it yet, Boeing is finally ready to say that the V22 Osprey tilt rotor is ready for prime time, by bringing it to the Farnborough Air Show.

"Bringing it"? Better than that: they flew them there from Goose Bay

Poor choice of words. I didn't mean to intimate that they had been taken there as cargo. Flew 'em. Only one made it all the way, but they flew 'em.

Elspode wrote:

Poor choice of words. I didn't mean to intimate that they had been taken there as cargo. Flew 'em. Only one made it all the way, but they flew 'em.

Yeah...I knew how you meant it; but wanted to clarify. The V-22 has gotten a bad rep I don't think it deserves; considering what a radical advance it is the problems have actually been rather few.

The only thing I like about that VTOL machine is that it's named after my favorite bird. It's hard to imagine just what role it's supposed to have in today's war theaters. It seems to me like a "jack of all trades, master of none" kinda thing.

The V-22 has gotten a bad rep I don't think it deserves

Perhaps, Maggie, but I've read that about 20 guys have died in about 4 different accidents in the development of that thing, and billions and billions have been spent. Let's hope the improvements at least make it safer, but I still like the bird it's named after better.:neutral:

Pangloss62 wrote:

Perhaps, Maggie, but I've read that about 20 guys have died in about 4 different accidents in the development of that thing, and billions and billions have been spent. Let's hope the improvements at least make it safer, but I still like the bird it's named after better.:neutral:

And how is it radically different from the British Harrier VTOL?

Pangloss62 wrote:

Perhaps, Maggie, but I've read that about 20 guys have died in about 4 different accidents in the development of that thing, and billions and billions have been spent.

There was one prototype lost at Wilmigton because a mech wired the controls backwards. There was an inflight fire because drains on the rotating cowlings weren't properly designed. There have been I think two lost due to problems with pilot technique; the tiltrotor configuration has some unique failure modes; if you decend too fast without sufficient forward airspeed, for example.

But the advantages to tiltrotor are considerable: how about a commuter airliner that can operate from a helipad in a downtown area, for example?

Developing a completely new kind of aircraft does involve both risk and money. Ask Wilbur and Orville,Sikorsky, Mort Taylor, the crews of Apollo 1 and 13, Challenger and Columbia.

Spexxvet wrote:

And how is it radically different from the British Harrier VTOL?

Well, it's not a jet fighter-bomber....it's in some ways a helicopter derivative. Rotary wing, etc.

Probably scads more fuel efficient, expecially in hover. More lift capacity, slower airspeeds. Vastly cheaper to operate. Won't deafen people on the ground near a landing site. (Ever been around a Harrier in hover at low altitude? I have.)

Basically how a Ferrari is radically different from a diesel bus.

Basically how a Ferrari is radically different from a diesel bus.

Exactly! The Ferrari is very expensive, very complicated, and needs lots of service while the diesel bus is a cheap and dependable workhorse that rarely breaks down.

I can't see how the Osprey would be a better commuter craft than existing helicopters. In combat, troops cannot rappel out of that craft like they can in helicopters. I'm all for innovation, but how long have they been trying to perfect that Osprey? How many billions of dollars?

It seems to me that the best air machines are those that are dependable and last forever:

Huey UH-1
Hercules C-130
F4 Phantom

You know, aircraft like that.:o

Spexxvet wrote:

And how is it radically different from the British Harrier VTOL?

It doesn't work. ;)

It doesn't work.

:biglaugha

Pangloss62 wrote:

Exactly! The Ferrari is very expensive, very complicated, and needs lots of service while the diesel bus is a cheap and dependable workhorse that rarely breaks down.

Well, that's fine...but I was thinking of the Harrier as the Ferrari.

Not that the Harrier hasn't served well; it's a remarkable aircraft; its performance in the Faulklands was noteworthy. But it's designed for a completely different purpose.

The one I saw on display at the National Maritime Museum at Greenwich had a plaque noting that they will be replaced with the VTOL version of the JSF.

Happy Monkey wrote:

It doesn't work. ;)

Erm....actually it does.

Pangloss62 wrote:

I can't see how the Osprey would be a better commuter craft than existing helicopters.

Well, that's a failure of your perception. Compare the speed, lift and operating range of the V-22 to "existing helicopters".

In combat, troops cannot rappel out of that craft like they can in helicopters.

Really? Why? This will come as quite a surprise to the troops who have done it.

MaggieL wrote:

Erm....actually it does.

Well, of the two that were sent to the show, one does.

I'm rooting for it, though. It's a cool idea.

Happy Monkey wrote:

Well, of the two that were sent to the show, one does.

Apparently the one that had problems diverted to Iceland. Whether it eventually continued on to the show I don't know. But if everything isn't beleved to be working perfectly on an Atlantic crossing, a precautionary landing is a Very Good Idea.

No doubt.

Didn't Gloster develop something exctremely similar in the late '50s?

JayMcGee wrote:

Didn't Gloster develop something exctremely similar in the late '50s?

Similar to the V-22? Or the Harrier? In either case, not that I'm aware of. Apparently Gloster's big entry in the late '50s was the Javelin fighter, but that wasn't VTOL. Closest in that era were probably the Lockheed XFV-1 and Convair XFY-1, neither of which was particularly successful, being *very* difficult to fly.

The V-22 control system is very impressive.

Pre-dates the harrier. The craft I''m thinking of was very much like the boeiing thing, but the blades were a fan-blade configuration. All else was the same.
It may never have made it off the drawing-board, but the concept was all over 'Flight' magazine in the mid-late 50's

Fairey Rotodyne or Gyrodyne maybe. With the Gyrodyne you're getting into autogyo territory...which is interesting to me because Pitcairn and Kellet were local fellows who was very active in developing Cierva's autogyro concept. I've seen his "Miss Champion" fly...and you may have seen it in the film "The Rocketeer".

Pitcairn's "Pitcairn Field" airport was eventually donated to the US Navy to become Naval Air Station Willow Grove, just north of Philly.

This will come as quite a surprise to the troops who have done it.

Well you got me on that one:redface:

I read somewhere that the downwash velocity from those props prohibitted that, but that photo clearly shows that's not the case. Nonetheless, other problems like vortex ring state rolling and lack of autorotation in case of power failure make it an expensive and risky craft.

Pangloss62 wrote:

Well you got me on that one.

I read somewhere that the downwash velocity from those props prohibitted that, but that photo clearly shows that's not the case. Nonetheless, other problems like vortex ring state rolling and lack of autorotation in case of power failure make it an expensive and risky craft.

If the downwash from a V-22 made rappeling impossible, how could it possibly work on a conventional helo? How totally bogus.

Sounds like you've absorbed a lot of "read somewhere" uninformed criticism from the mainstream press...of which there's a lot. I referred to the vortex ring issue earlier...and hey, guess what: no fixed-wing aircraft can do an autorotation either.

If you're aware of a case of total power failure in a V-22 let me know about it; there's two redundant engines and the transmission is designed such that either engine alone can drive both rotors. That's superior to most conventional multiengine arrangements.

Sounds like you've absorbed a lot of "read somewhere" uninformed criticism from the mainstream press...

Most of what I've read has come from USAF and Marine personel, technical specialists, and aircraft engineers that have been involved with the development of the V-22. Unless you're a V-22 pilot, your likely going to get information on the craft from something you "read somewhere." I could only assume that with billions and billions at stake, Boeing and Bell's "information" is just as likely to be propaganda as anything "the mainstream press" reports. And if those engines are so great, why did one of those two Ospreys going to the show have to land in Iceland after "right engine compressor stalls" and have the entire engine replaced?

I'm not trying to pick a fight with you, Maggie, I just think there are still many unresolved issues with the craft, and that taking 25 years, 27 lives, and 20 billion to get to this point is a bit much. :neutral:

Pangloss62 wrote:

I just think there are still many unresolved issues with the craft, and that taking 25 years, 27 lives, and 20 billion to get to this point is a bit much.

Had this been any other type plane, it would have been quashed long ago. The Osprey has a reliablity record that is and promises to be as bad as the F-111. So what keeps the Osprey alive? It is a unique design desperately needed by ground forces. That's it. There is no other replacement and the need it that large. Not for many sales of these aircraft. But some are needed.

Had it been designed properly, the Osprey could have been extremely profitable. But the aircraft was chock full of little problems that were easily avoidable such as hydralic hoses that pinched off as the rotors tilted. Complicated engineering problems did not cause so many problems. It was the simplest of problems that condemned this otherwise extremely necessary aircraft to lesser sales.

Even the F-111 did not have reliability failures found in the Osprey. The F-111 was so unreliable that twice the number required were flown on the Libya attack. Then the half that were still working off the coast of Spain continued on to the attack. F-111 maintained a reliability grade of D because of how it was designed. Unfortunately Osprey reliablity may always remain bad.

Funny you mention the F-111. I was listening to the Austalian Broadcasting Corp. on my shortwave the other night and heard about an emergency landing; now the fleet is grounded:

[COLOR="Navy"]F-111 fleet groundedJuly 19, 2006
AN investigation into Australia's F-111s begins today after the 26-strong fleet was grounded following an emergency landing in Brisbane by one of the ageing strike bombers.
The aircraft made a belly landing at the RAAF's Amberley base west of Brisbane about 2.10pm (AEST) yesterday after losing a wheel on takeoff.

After circling the air base near Ipswich for almost three hours to burn off excess fuel, the jet came into land, creating a plume of sparks as it slid on its belly along the tarmac.

The 29-year-old pilot had only graduated from the F-111 training course two weeks ago, but his 32-year-old crew member is considered one of the most experienced F-111 navigators.

Defence Minister Brendan Nelson said the grounding of the F-111 fleet was necessary to ensure there was nothing structurally wrong with the planes.

Air Marshall Geoff Shepherd said it was the first time a wheel had ever fallen off an F-111 in the 30-year flying history of the planes in Australia.

He said there were still no clues as to why the wheel fell off as the jet took off on a routine flight to Tenterfield in northern NSW.

RAAF Amberley's Group Captain Leo Davies believed it may only take weeks for the investigation to be completed.

"Defence's flying safety investigators, Boeing - as the primary contractor for F111 maintenance - and a Melbourne-based team of engineers will head the investigation," he said.

"They will determine what happened and also assess how much work needs to be done and the time frame to get the aircraft back in the air again.

"They should make an assessment over the next few weeks."

Eight F-111s have crashed since they began operating in Australia in the 1970s, killing 10 crew. [/COLOR]

tw wrote:

Had this been any other type plane, it would have been quashed long ago.

Precicely.

It *isn't* "any other type of plane". It is an entirely new category of aircraft, which is why the development has been so tortuous...combined with the fact that the development has occurred (necessarily) within the largest buracracy on the planet. It's amazing that they ever get anything done.

FB-111 is a case in point: DoD civilian management (in the person of Robert MacNamara, as I recall) decreed that the next big tactical aircraft would be a joint Air Force-Navy design. After years of grunting, groaning and failed designs, Navy rebelled, gave up on the joint program, took the systems that were salvagable and created the F-15...arguably an *extemely* successful military aircraft acquisition, even though the Panglosses and TWs of the time harped just as loud about exactly the same things they're screeching about now.

You guys sure you don't want to say a few words slagging the Joint Strike Fighter program now? :-) After all, it will finally accomplish what MacNamara dictated (a joint tactical aircraft)...now that computational technology is actually up to the task of producing the design, flight-control and sensor systems needed. And one variant from that program is planned to replace the Harrier, which kinda brings it all full-circle.

Just as a sidebar, I think the most important reason there have been 27 fatalities in the V-22 program is that 19 of them were in *one* fully-loaded Osprey that was lost because the pilot flagrantly violated a rate-of-decent limit and entered the ring-vortex state. You can lose a whole *pile* of people in one transport aircraft accident, because they carry a lot of people.

(The hardest thing about any radical new aircraft design is finding out how *not* to fly it. F-15 had a similar flight envelope problem involving compressor stall, as I recall). The V-22 flight control software has been rewritten to keep the aircraft out of that failure mode.Look at the civilian Robinson R-22....nice little piston powered helo with composite main rotor. But maneuver it wrong and the main rotor blades will strike the tail boom. Try and autorotate out of that one...

That April 2000 V-22 loss was during a simulation of a Non-combatant Evacuation Operation...one of the V-22's primary missions. Would have been nice to have a few V-22 squadrons operational for the current NEO in Lebanon, but it was not to be. In fact, some view the creation of V-22 as a direct result of the failure of Carter's Desert One NEO debacle.

the Panglosses and TWs of the time

We've been typecast!:neutral:

If we're harpies, what are you? I would guess a sage.:notworthy

No, you just have to miss the ground, or forget to hit it.

tw wrote:

Had this been any other type plane, it would have been quashed long ago. ...

And here I thought it was alive because it was in Curt Weldon's district.

Only half, the other half is in Texas. ;)
From the Dallas Morning News;

The Marines are eager to get the Osprey to replace troop transport helicopters whose maximum speed is about half the V-22's and whose range is much shorter.

"We're using this opportunity to do a rehearsal for what we're going to do next year," said Lt. Gen. John Castellaw, deputy commandant of the Marine Corps for aviation.

'Remarkable flight' Lt. Col. Christopher Seymour, 42, of Houston, one of four pilots from the Marines' tilt-rotor test squadron, VMX-22, who made the first trans-Atlantic crossing by tilt-rotor aircraft, said the journey was "a remarkable flight."

Accompanied by two Marine Corps KC-130J tankers, the Ospreys refueled three times during the flight from Goose Bay, Canada. They were accompanied by a third Osprey in case of problems.

"I'm reluctant to say it was historic, but hopefully it will be historic," Col. Seymour, VMX-22's executive officer, said of the ocean crossing. "Maybe this will become a routine mission for the Marine Corps and all the operators of the V-22 and tilt-rotors."

The quest to recast the Osprey's image was tarnished when Col. Seymour's Osprey suffered compressor stalls in its right engine. He and co-pilot Col. Glenn Walters, commander of VMX-22, landed in Iceland.

They were midway through the scheduled nine-hour trip when the compressor stalls - a disruption of the airflow into the Osprey's jet-driven turboshaft engines - caused the right engine* to shut down for two or three minutes, Col. Seymour said.

They restarted the engine and flew on for two more hours, he said, but decided to set down in Iceland when the Rolls-Royce AE1107C engine suffered yet another compressor stall, though it kept running.

"That's when we made the decision," Col. Seymour said. He said that knowing how the diversion might be viewed by the V-22's critics, "I was second-guessing myself all the way into Keflavik."

"If we were going to war, we probably would have pressed on to Farnborough," he said.

Col. Seymour and V-22 program officials at Fairford said Friday that the other Osprey that flew on to Farnborough experienced similar but less serious "compressor surges" in one of its engines, as did the spare Osprey that flew back to North Carolina from Goose Bay.

The Marines flew a spare engine already positioned in England to Keflavik and replaced the right engine in Col. Seymour's Osprey. It finished the trip to Farnborough only 36 hours after landing in Iceland, he said.

Relatively common The V-22 program manager, Col. William Taylor, noted that compressor stalls are relatively common in jet engines, including commercial airliners.

"It's not something mechanical," Col. Taylor said. "It's a burp; it's an interruption of the airflow."

During most of the trip, the pilots put their Ospreys on autopilot, Col. Seymour said.

"We had to do things to keep ourselves entertained for the nine hours," he said. "We told stories, we ate, we snacked. We brought an ice chest with sodas and water and stuff like that."

His greatest disappointment with the flight was media coverage of the compressor stalls, focusing on that instead of the "remarkable accomplishment" achieved by the crews from VMX-22 and those of the tankers that flew with them.

Those engines are $2million...each.

From the beginning the two biggest problems have been weight and materials.
The original development contract had rigid standards on the materials that could be used. They specified composite materials that DRPA had thoroughly tested, for 5 years. This was in the early 80s when the composite technology seemed to be making strides every month. Starting with "antique" material made the weight/strength balance very difficult.

All the hydraulic tubing is titanium to save weight. On the computer models it was way stronger than necessary, but in practice it had to be thicker when they actually flight tested it.

Unlike any other aircraft, every fastener must be installed perfectly. There isn't enough redundancy for a bunch of other fasteners to take up the slack if you have a few installed sloppily....weight again.

There has been so many threats to cancel this program, the Marine Corp wants so badly, they were pushing implementation to the max. Remember the marines are not flying Chinooks but the much smaller, older, Sea Knights, which puts them way behind the Army Rangers. Inconceivable.

I think they could have avoided half of the deaths by using sand bags instead of troops while the pilots were learning the flight envelope for this aircraft.
I'll stop now.

xoxoxoBruce wrote:

I think they could have avoided half of the deaths by using sand bags instead of troops while the pilots were learning the flight envelope for this aircraft.
I'll stop now.

They could have avoided 19/27 (clearly more than half) of the deaths if the *one* pilot had stayed inside the already known flight envelope.

Speaking of lighter materials and composites, another aircraft flew at Farnborough

An unmanned aircraft made from "printed" parts rather than traditional machine-tooled components has been unveiled at the Farnborough Air Show, UK.

Developed at Lockheed Martin's top-secret "Skunk Works" research facility in Palmdale, California, US, the Polecat unmanned aerial vehicle (UAV) is a 28-metre flying wing, weighing four tonnes. It was designed in part to test cheaper manufacturing technologies.

xoxoxoBruce wrote:

They specified composite materials that DRPA had thoroughly tested, for 5 years. This was in the early 80s when the composite technology seemed to be making strides every month. Starting with "antique" material made the weight/strength balance very difficult.

So, if they hadn't done that the shrieking would be about how much blood and treasure had squandered on "new, untested materials tech".

Bringing new tech into aviation is always an ugly struggle between innovation and safety, between a desire to used the newest, best stuff available and the competing desire to use only what is known and well-understood.

Avionics has been a prominent arena for this...and the Space Shuttle computers are an obvious case in point. Only now are we seeing glass cockpits seriously beginning to displace "steam gauge" panels. The same applies to materials--for example lightning protection has been a huge cause celebre where non-conducting composite materials are concerned. And how to successfully *repair* minor damage to composite parts is still a new field.

Geting a new technology to the point where lives can be trusted to it is nearly impossible to do without actually trusting lives to it. And as always, it's ever so much easier to criticise from an armchair on the sidelines after engineering decisions have been made. Of course, if someone's initial motivation is to find something to carp about, something can always be found. It's so unthinkable for the media to recognize that this mission was successful (which won't sell as well as "Military Procurement Scandal Wastes Lives!") that the story is somehow now all about compressor stalls and a precautionary landing.

Hey Maggie, what kind of job do you have? Regardless of our opinions, it's fun to talk aviation technology with folks that have an interest. Mine stems from my father's career at Lockheed. I spent much of my youth reading Aviation Week & Space Technology and looking through all the Janes' books I could get my hands on. And then there were the models; lots of model plane building. I think you can learn a lot about aviation just by building models (though I don't do that these days).

I'm really interested in the aesthetics of aircraft design, especially jets. The Korean War-era jets look so cool to me, and all Cold War-period technology fascinates me. I just finished working on a National Register Nomination for a Nike base, and in doing so I learned a lot. Do you have a favorite aircraft?

Pangloss62 wrote:

Hey Maggie, what kind of job do you have? ... Do you have a favorite aircraft?

Well, by profession I'm a software engineer, currently working on Java-based control software for a high-performance blade cluster used in the insurance industry.

But I have a life-long interest in aviation and astronautics. My father was a clergyman, but he was also an elementary school science teacher during the Sputnik era, so that was a big influence on my interest in aviation, astronautics, computing and radio and electronics.

I've been active in space-based amateur radio at various times, and have logged contacts though amateur radio satellites and with the crew on board the International Space Station.

I can do no different than claim Cessna Cardinal N19762 as my favorite aircraft, because I own 10% of it and fly it on a semiregular basis.

More details at http://voicenet.com/~maggie

Twice as fast, twice as far and twice the payload than what the U.S. marines have today. That's the Osprey selling point. The key will be its use in Iraq starting next year.

Well, I hope they have worked the bugs out, because Iraq will be one hell of a test bed.

Don't forget to write Bruce.;)

No shite, RL. I was thinkin about that. Desert landings with two major downwash vorticies, not to mention its vulnerability to enemy fire (noise, size, target value, etc.). As a taxpayer, I feel I have no say in the matter. Same with the F-22. I just hope they can separate the pork from the engineering and science on both of these craft.

Maggie wrote:

Avionics has been a prominent arena for this

Yes, the military is just starting to realize that off the shelf avionics, that commercial aviation have proved reliable for about a jillion air miles, might work as well as the ones they were having built.....at 100 time the price. Well duh.

I guess nobody was willing to tip the sacred cow of Mil Spec.:rolleyes:

xoxoxoBruce wrote:

Yes, the military is just starting to realize that off the shelf avionics, that commercial aviation have proved reliable for about a jillion air miles, might work as well as the ones they were having built.....at 100 time the price. Well duh.

I guess nobody was willing to tip the sacred cow of Mil Spec.

If you took a little time out from bashing the military, you'd might realize that civil aviation has nearly as big a problem adopting new tech.

The advantage they have is their development cycle times tend to be shorter...largely because they don't have as big and motivated a journalistic peanut gallery to kibbitz and "mil-spec" oversight and procurment procedures to make sure the taxpayers largesse is "equitably and justly" distributed.

Allowing for that they're just as conservative.

I'm not military bashing by questioning the antique process of Mil Spec. It was devised to assure a quality product from lowest bidders by micro-managing every step and a paper trail a mile long. That's why we get $500 hammers and $800 toilet seats.

Once the avionics is being used commercially for a while and proven reliable, they know what they are getting. They don't have to reinvent the wheel, just because it's not Mil Spec. :rolleyes:

There's much more wrong with military procurment than MilSpec. MILitary SPECifications call for more durability and reliability than their commercial counterparts, and rightly so.

The $600 P-3 replacement toilet seat and "unidirectional impact generator" hammer of the 1980s were created by other parts of the procurement process...most especially the accounting rules that allowed burying additional "overhead" into the pricing of routine spare parts and tools associated with big-ticket projects. MilSpec isn't at fault there.

There *is* additional cost associated with any part used in civil aviation. It's partly due to meeting FAA certification rules...but mostly due to paying off trial lawyers who sue any deep pockets found in the aftermath of an any aircraft accident.

I'm just happy to see anything about this aircraft that is not about it killing someone.

Pangloss62 wrote:

Desert landings with two major downwash vorticies, not to mention its vulnerability to enemy fire (noise, size, target value, etc.).

In which it's comparable to the helo's its replacing...while in hover near the LZ. Where's it's expected to shine over the competition is flying faster/higher/farther while enroute, which reduces its vulnerability to ground fire. Having greater range keeps it away from the ground more also.

When you talk about "desert landings", remeber that this design is largely a result of lessons lerned at Desert One. Running *anything* mechanical in a sandbox is a challenge...but if it can be done this aircraft should be able to do it.

Pangloss62 wrote:

As a taxpayer, I feel I have no say in the matter.

Actually, I'm glad we don't vote on these things. Would you fly in an aircraft designed by the same process that gave you the government? :-)

Pangloss62 wrote:

I just hope they can separate the pork from the engineering and science on both of these craft.

As Rocky said to Bullwinkle, "That trick never works." But we can hope for enough separation of dreck from tech that something is delivered that's comparable to the DC-3, the B-52 or the F-15.

I like the idea of the Osprey but I'm wondering if we're getting into another Hummer situation? Is it a vehicle that's a little too big and a lot too expensive for its intended purpose? The Marines are still going to need smaller cheaper craft for hot lzs are they not?

Griff wrote:

The Marines are still going to need smaller cheaper craft for hot lzs are they not?

I don't see why. If an LZ is too hot for a V-22, what else would you send in to get shot up? Helos aren't expendable.

At least a V-22 is less vulnerable and less likely to be tracked visually/aurally enroute.

The Marines are still going to need smaller cheaper craft for hot lzs are they not?

The only aircraft I can think of for a hot lz would be an A-10...but that would take a lot of trips. :D

One of the advantages of the V-22 over the Ch-46, is they can launch from a ship on excursions further inland, then evacuate back to the ship. The ship is a safer base than they'd have in hostile territory.

xoxoxoBruce wrote:

The only aircraft I can think of for a hot lz would be an A-10...

And LZ isn't an LZ unless you can L there. Is there a secret VTOL version of the A-10?

Did he say there was a limit on the size of the lz? :eyebrow:

xoxoxoBruce wrote:

Did he say there was a limit on the size of the lz?

When an LZ exceeds certain size and surfacing constraints it's referred to as an "airport".

Wrong, open ground that a plane can set down on is not automatically or necessarily an airport. But you know that already, your just being a pain in the ass. :eyebrow:

xoxoxoBruce wrote:

Wrong, open ground that a plane can set down on is not automatically or necessarily an airport

That comes under "surfacing constraints". Runway penetrators such as the Durandal
are tools for turning airports into LZs by exploiting those constraints.

Oh stop it. :rolleyes:

Well, this is a potentially important issue personally: I need to schedule my Biennial Flight Review soon--an every-two-years checkride with an instructor pilot--and it's quite likely at some point during the flight check he'll pull the engine power and tell me I've just lost the engine, to see me go though the engine-out drill. This includes selecting an airport within gliding distance...possibly one whose owner doesn't know it's an airport. :-)

Selecting an LZ instead is considered bad form unless it's the only option.

mnmmm......

Back in the '60s, me dad was stationed at RAF Macrihanish, on Kintyre..

At that time, it had the longest runway in the UK, at around the two mile mark.

After we left, NATO (via the USAF) took over the base.... and extended the runway.....

WTF requires a LZ over two miles long?

If the runway is very long, they can still use portions if someone tries to sabotage it.
You can line up a shitload of bombers and take off in rapid succession.
Same with landing, when they have a long way to rollout
Could be an alternate landing site for the Space Shuttle. ;)

JayMcGee wrote:

WTF requires a LZ over two miles long?

Rumors have F-117s, "Aurora" aircraft and a Navy SEAL detachment operating out of Machrihanish. It's not inconcievable to me that it might have been spruced up as an alternate landing site for SR-71s from the 9th Strategic Reconnaisance Wing Detachment 4 at RAF Mildenhall...if an SR-71 was inbound and Mildenhall suddenly went below minimums or was closed by an accident, it would be nice to have somewhere else private to go without refueling....refueling an SR-71 midair is not a trivial undertaking. In Spring 2005 Machrihanish was NOTAMed for a parachute drop which apparently never happened due to WX.

Two miles sounds like a lot of runway, but 3,000' is a nice comfortable distance for my Cardinal (although it can certainly operate in about half that length if necessary). 27L at KPHL is over 10,000 feet long, and it's typical of largish airports in the US. All runways at the new (for an airport) KDEN are 12,000 feet long. The Shuttle Landing Facility rwy 5/33 at KSC is 15,000 feet long, and it's beleved to be the longest in the world.

While there is information online about US enhancements at Macrihansih, including a new tower, there's no mention of runway lengthening. Looking at Google Maps the biggest runway in the area of Macrihanish looks to be no more than 10,000 feet...is there another big airport nearby? Maybe I'm looking in the wrong place.