VTOL - Verbiage and Videos

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TheGreenGoblin
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VTOL - Verbiage and Videos

#1 Post by TheGreenGoblin » Sun Mar 13, 2022 7:39 am

The Yakovlev Yak-141


Cooperation with Lockheed
Following the announcement by the CIS on September 1991 that it could no longer fund development of the Yak-41M, Yakovlev entered into discussions with several foreign partners who could help fund the program. Lockheed Corporation, which was in the process of developing the X-35 for the US Joint Strike Fighter program, stepped forward, and with their assistance aircraft 48-2 was displayed at the Farnborough Airshow in September 1992. Yakovlev announced that they had reached an agreement with Lockheed for funds of $385 to $400 million for three new prototypes and an additional static test aircraft to test improvements in design and avionics. Planned modifications for the proposed Yak-41M included an increase in STOL weight to 21,500 kg (47,400 lb). One of the prototypes would have been a dual-control trainer. Though no longer flyable, both 48-2 and 48-3 were exhibited at the 1993 Moscow airshow. The partnership began in late 1991, though it was not publicly revealed by Yakovlev until 6 September 1992, and was not revealed by Lockheed until June 1994
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Re: VTOL - Verbiage and Videos

#2 Post by TheGreenGoblin » Mon Mar 21, 2022 5:23 pm

A man who is generally forgotten in the pantheon of the those pioneers who pursued the dream of VTOL...

Gerard P. Herrick
Born: United States of America
Primarily active in: United States of America

1873-1955

Gerard Post Herrick was one of the earliest to advocate combining fixed-wing flight with rotary-wing flight, a concept he initially called the Vertoplane and which has subsequently become universally denoted as the "convertiplane." He has been given little notice by vertical flight historians, quite unjustifiably becoming one of the "forgotten rotary-wing" pioneers, the champion of a concept that even today in various forms seeks legitimacy.

Gerard Post Herrick graduated from prestigious Princeton University with an A.B. at the age of 22 in 1895 and received his law degree two years later in 1897 from New York Law School. Interested in things mechanical, and keenly aware of the dawn of the age of manned flight with the Wright brothers, as information gradually became available of their 1903 flight, Herrick eventually committed himself to an aviation future in 1911 when he formed the Herrick Engine Company to promote his "balanced rotary engine" concept.

Herrick became interested in 1927 in the possibility of combining both fixed -wing and rotary-wing flight. Inspired by the early reports of the rotary-wing success of Juan de la Cierva, but rejecting Cierva's conceptualization of the "flapping hinged rotor", as he was already theorizing about combining rotary-wing flight and fixed-wing in a bi-plane arrangement where the upper wing would also become a rotor, Herrick developed the "symmetricallly cambered wing" that could produce lift while either fixed or rotating, and sought to combine this with the lower wing of a biplane that could either function in fixed or combination mode with the upper wing acting as a rotor.

In World War-I he was Captain in the US Army Air Service and had served eleven years with Squadron A of the New York National Guard. More recently he was a member of the Committee on Universal Military Training headed by General Adler.

Mr. Herrick was a member of : The Academy of Sciences, American Rocket Society, American Society of Mechanical Engineers, Army and Navy Club of Washington, D.C., Association of Ex-Members of Squadron A, New York City, Associate Member of Institute of the Aeronautical Sciences, Associate Member of Seventy-Seventh Division Association, Newcomen Society of North America, Princeton Club of New York City, Princeton Engineering Society, The Convertible Aircraft Pioneers, University Club of the City of New York, University Club of the City of New York, University Club of Winter Park, FL, University Cottage Club of Princeton, N.J., and the Wings Club of N.Y.C.

Gerard Post Herrick, President of the Convertiplane Corp., New York City, died at his home on September 9, 1955. Mr. Herrick was best known as an inventor and research engineer. Named the father of "Convertible Aircraft" at the first Convertible Aircraft Congress on December 9, 1949, sponsored by the Philadelphia sections of the Institute of the Aeronautical Sciences and the American Helicopter Society, he was awarded a plaque reading "in recognition of his inventing and building the first convertible aircraft, the Convertiplane, which was publicly demonstrated flying both as an aircraft with rotor wing fixed and as an autogyro with rotor wing rotating, at Niles, Michigan, Municipal Airport, November 6, 1931." The Convertiplane, which was publicly demonstrated at Boulevard Airport, Philadelphia, July 30, 1937, made its first conversion from fixed to rotating wing flight on that date.

"Gerard Post Herrick (1873 - 1955) America's Unforgettable 'Forgotten' Convertiplane Pioneer", Dr. Bruce H. Charnov Ph.D., J.D., Presented at the American Helicopter Society 63nd Annual Forum, Virginia Beach, VA, May 1 – 3, 2006"

https://vertipedia.vtol.org/biographies ... raphyID/18 <<vertipedia is a great resource>>
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Re: VTOL - Verbiage and Videos

#3 Post by TheGreenGoblin » Wed Mar 23, 2022 9:50 am

wheelwords.jpeg
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Re: VTOL - Verbiage and Videos

#4 Post by TheGreenGoblin » Wed Mar 23, 2022 10:57 pm

The Long Road to the Tilt Rotor...
Finding the practical solution to the engineering difficulties faced by making this concept a reality has been one of the greatest tasks facing aeronautical engineers and aerodynamicists in the last 75 years. It might come as a surprise that the original pioneers are not household names. William E. Cobey bought Transcendental Aircraft in 1952 and developed the Model 1-G single-seat tiltrotor under an Army/Air Force contract. The centrally mounted Lycoming O-290 piston-powered 1-G crashed as a result of pilot error in 1955, but not before flights had taken place where the prop-rotor drive shafts had been tilted to within 10 degrees of the horizontal airplane mode. This vehicle is recognized as the first to explore transition from vertical flight to wing-borne airplane flight.

Bell XV-3
The XV-3 convertiplane for the U.S. military was designed in 1951 as the Bell Model 200. The aircraft was the first to make the transition from helicopter to airplane mode, in 1958.
A founding father of Transcendental, Bob Lichten, later joined Bell Aircraft, and in 1951 designed the Bell model 200 that successfully competed for funds from the military for two “tilting thrust vector converti planes” as the XV-3. The XV-3 was similar in configuration to the 1-G, in that the Pratt & Whitney R-985 piston engine was centrally mounted in the fuselage and used drive shafts originating from a fuselage mounted transmission to turn the three-blade, 25-foot-diameter prop rotors. But with a its maximum takeoff mass of 4,700 pounds, the aircraft was almost three times the weight of the Model 1-G. The prop rotors were mounted at the end of long drive shafts, a placement that, coupled with fully articulated rotors and an unbraced wing structure, led to rotor instability and very heavy airframe vibration. These factors caused a crash of the XV-3 during a flight in October 1956. The pilot, [b**]Dick Stansbury[/b], lost consciousness as a result of airframe vibration during an attempt to expand the flight envelope with the rotors tilted forward at an angle of 17 degrees.

The company made a number of modifications to the XV-3 that enabled test pilot Bill Quinlan to complete the first full transition from helicopter to airplane mode in December 1958.
The thinking underpinning the helicopter and tilt rotors etc. has always been a little "out there" vide. the father of the Bell 47... Arthur M Young
In 1976, Young's theory of evolution of life on Earth — which attempted to synthesize understandings from geology, biology, anthropology, psychology, and parapsychology — appeared under the title The Reflexive Universe. Young accepted the general "theory of evolution," but pointed out where he felt the Darwinian theory was insufficient to the facts. The book also incorporates a brief speculative discussion of further human psychological and spiritual growth.
** Stansbury broke his back in the accident and was left partially paralyzed for the rest of his life, but undeterred, he became a key engineer in the technology that underpinned the Bell XV-5 programme that has led directly to the V 22 Osprey.







^:)^
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Re: VTOL - Verbiage and Videos

#5 Post by TheGreenGoblin » Sat Mar 26, 2022 11:34 am

This VTOL story is still in the news...

viewtopic.php?p=324562#p324562

Joby1.JPG
Joby Aviation says that the prototype aircraft which crashed during a flight test last month was pushing its flight envelope limits when it went down.

At the time of the accident on 16 February the aircraft had been “engaged in an envelope expansion campaign” Joby founder and chief executive JoeBen Bevirt says on the company’s quarterly earnings call on 24 March. “That’s normal for flight testing.”

The Silicon Valley-based company is developing an all-electric vertical take-off and landing (eVTOL) aircraft with five seats that is planned to have a maximum range of 133nm (241km) on a single charge and travel at a top speed of 178kt (321 km/h).

Flight tracking data at the time of the accident showed that it was travelling much more quickly than that top speed.

We were at the end of the flight test expansion campaign and test points that were well above what we expect to see for normal operations of the aircraft,” he adds.

The National Transportation Safety Board (NTSB) is investigating the accident, so company executives were reluctant to release any further details.

The NTSB had said on 17 February that the crash occurred in Jolon, California, which is located in a rural area about 174mi (280km) south of San Francisco, a day earlier. Two weeks ago, the safety agency said in a preliminary report that the mishap was due to “a component failure”.

Joby earlier on 24 March announced the resumption of the flight testing programme with a second aircraft, after a five-week pause. That second prototype first flew in January. To date, it has made 38 flights.

“We’re excited to be back in the air with our second pre-production prototype aircraft, building on the tremendous flight test achievements our team has made to date,” says Didier Papadopoulos, Joby’s head of programmes and systems.

The company is looking to “build on the momentum” that it had when the accident occurred.

“Ensuring that we continue to do that work over the next quarters to prepare for the final certification efforts is one of the key goals of that vehicle,” Bevirt says. The company adds that it does not expect the aircraft’s loss to have “a meaningful impact” on its timeline for certification.

”Certification is understandably a complex and multifaceted process,” adds Papadopoulos.

Joby’s main focus in 2022 will be on certification and early manufacturing.

“We plan to expand our facilities at our pilot manufacturing plant to support building the first aircraft on our production line as well as additional parts for certification and other operational requirements,” the company says in its fourth quarter earnings report. The first ”production-intent” airframe is due to fly this year, executives add.

Last week, Joby had said it had also successfully completed several FAA reviews at the end of last year.

“The systems review assessed Joby’s plans and process for the development of complex, safety-critical, aerospace-grade systems and equipment,” the company had said on 18 March. “Systems involved in the review included flight controls, propulsion controls, battery management, among many others.”

“The compliance review evaluated Joby’s approach to the development and verification of aerospace-grade software and airborne electronic hardware.”

The company has therefore made “good progress” towards securing its Part 135 air carrier certification. Joby has said it expects to receive the certificate, which is required to operate the aircraft as an air taxi service - in the second half of 2022 as planned. It’s aiming to launch its air taxi services in 2024
https://www.flightglobal.com/safety/job ... 43.article
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Re: VTOL - Verbiage and Videos

#6 Post by tango15 » Sat Mar 26, 2022 10:43 pm

During the process of getting the 125 certificated in Russia, one of the people I worked with was a former Russian Navy pilot. We became good friends and occasionally went out for dinner together. One such evening, the subject turned to the Falklands and the concept of 'VIFFING'.* He told me, and I have no corroboration for this, but equally have no reason to doubt the story, that they once went on an exercise in the Black Sea, probably with the Kuznetsov, which was undergoing trials at the time, with the intention of emulating the Harrier's capabilities. Anyway, they took with them a number of Yak-38s and tried to simulate the 'viffing'. It was not at all successful, and after they had lost five aircraft one the first sortie and three on the second, they decided to return home. Following this, the Yak-38 was 'retired'. Unofficially, they decided that there just wasn't enough power in one of those Turmansky engines, so they fitted a second engine, this time a Rybinsk duo, with similar power, giving a total of 14,200 lbf (31.9 kN), as opposed to 21,800 lbf (97.0 kN) with the Harrier. QED!

*Vectoring in forward flight, for anyone not familiar with the acronym.

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Re: VTOL - Verbiage and Videos

#7 Post by TheGreenGoblin » Sun Mar 27, 2022 1:19 am

tango15 wrote:
Sat Mar 26, 2022 10:43 pm
During the process of getting the 125 certificated in Russia, one of the people I worked with was a former Russian Navy pilot. We became good friends and occasionally went out for dinner together. One such evening, the subject turned to the Falklands and the concept of 'VIFFING'.* He told me, and I have no corroboration for this, but equally have no reason to doubt the story, that they once went on an exercise in the Black Sea, probably with the Kuznetsov, which was undergoing trials at the time, with the intention of emulating the Harrier's capabilities. Anyway, they took with them a number of Yak-38s and tried to simulate the 'viffing'. It was not at all successful, and after they had lost five aircraft one the first sortie and three on the second, they decided to return home. Following this, the Yak-38 was 'retired'. Unofficially, they decided that there just wasn't enough power in one of those Turmansky engines, so they fitted a second engine, this time a Rybinsk duo, with similar power, giving a total of 14,200 lbf (31.9 kN), as opposed to 21,800 lbf (97.0 kN) with the Harrier. QED!

*Vectoring in forward flight, for anyone not familiar with the acronym.
I leave it to those who have "viffed" here to comment from the basis of experience, but the fact that the Yak-38 carried the weight of the essentially fixed lift jets and, initially only the single RD-27 vector thrust engine, probably made it difficult to emulate the far more versatile Harrier.

I wonder how useful "VIFFing" actually was in combat scenarios?

As you say tango15, the Yak-38 was a severely compromised VTOL military aircraft.
The Yak-38, code-named Forger by NATO, actually entered service in 1976, three years earlier than the Sea Harrier. Like the British plane, it could fly just short of the speed of sound, at around 680 miles per hour. Unlike the Harrier, it had two dedicated lift jets behind the cockpit in addition to a single RD-27 vector thrust engine; the additional jets resulted in higher fuel consumption, limiting range to around two hundred miles at best, and less if it performed a vertical takeoff. The Soviet Union produced 231 Yak-38s, including fifty-two upgraded Yak-38Ms in the 1980s with more powerful R-28 engines and more rugged landing gear.

The most important differences between the Yak-38 and Sea Harrier aircraft lay in payload: the Yak-38 had no radar, limiting its potential as a fleet defense fighter. Its air-to-air armament was confined to small R-60 heat-seeking missiles with a maximum range of five miles, as well as optional twenty-three-millimeter cannon pods. For ground attack, the Yak-38 had just four underwing hardpoints for bombs or unguided rockets, and had a small maximum bomb load between one thousand and two thousand pounds—about one-quarter of what the Harrier could carry. The Forger could also launch Kh-23 antiship missiles with a range of a few kilometers, but the Forger’s pilot would have had a difficult time controlling the manually guided weapons without a back seater.

It did not help that jump jets are even more complicated, and more accident prone than regular fighters. By the end of the Kiev’s first cruise with Yak-38s on board, only one of the six aircraft embarked was operational. The temperamental Forger was unpopular with pilots, too. The Yak-38’s designers had observed that if one lift jet broke down, the other would spin the aircraft over on its side. To protect the pilot, an automatic ejection system was designed to detect sharp changes in pitch and immediately eject the pilot at an angle away from the carrier’s forecastle. Predictably, this well-intentioned safety measure was triggered unnecessarily on many occasions, causing a loss of the airplane and the pilot’s career prospects.

What was the Yak-38 actually good for? Certainly, it would never have wanted to tangle with a proper fighter like the F-14 Tomcat, with more than twice the speed and longer-range armaments. Nor did NATO have a large fleet of maritime bombers like the Tu-95 Bear, though the Forger could have been used to hunt down lumbering P-3 and Nimrod patrol planes. Russian sources often characterize the Forger as a “Sturmovik” (attack plane), and it could have conducted limited ground strikes, though its applicability in a NATO–Warsaw Pact confrontation would surely have been limited.

But could have Yak-38 have been used from forward airfields on land, as envisioned for U.S. Marine Corps Harriers? In fact, the Soviet Union tested out the concept when it deployed four Yak-38s for combat missions in Afghanistan in 1980s, and some sources maintain participated in a few air strikes targeting the mujahideen, though details are scant.

Overall, though, it did not go well. The Forger’s engines had difficult performing in high temperatures, the heat from the lift jets rapidly damaged takeoff surfaces and kicked up tremendous dust that clogged engine intakes. In the end, the Yak-38 simply lacked the range and weapons load of alternative such as the Su-25 Frogfoot attack plane. While the Yak-38 could have used its jump jets for pop-up attacks like a Hind attack helicopter, it would have been just as easy to hit and far less well armored. To be fair, however, a Yak-38 veteran in the documentary clip below argues that these problems could have been overcome with persistence and that the Forger had potential, but Soviet commanders felt otherwise.
- Yak 38



Follow me class, let's conjugate the verb... I viff, you viff, he viffs etc.

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Re: VTOL - Verbiage and Videos

#8 Post by Boac » Sun Mar 27, 2022 9:33 am

Ah! Viffing. Great fun and in the right place extremely useful. I have a vague recollection of posting about it before, but cannot find it....

It enabled two things - one was a dramatic change in airflow over the tailplane as the nozzles were put down. Secondly it activated the 'puffer controls (active with 20+deg nozzle).

The unmentionable third effect was the ability to wash speed of the airframe quicker than you ever thought possible :)) For example, use of full power and the nozzles to the 'braking stop' (slightly forward) would throw you against your straps as the jet decelerated.

So, when to use it?

Tracking a target for a guns or (later) a missile kill but you are unable to quite get the turn rate to put the pipper on the back of the pilots head - a brief 20 deg application gives a huge pitch up, plus enhanced nose-raising ability via the puffers. Press and release the firing button and send off for another 'kill' sticker for the side of the cab.

Being tracked and feeling a hot gun/missile sight pipper getting near the back of your head - a bit more nozzle and some deft stick work and bam! Your speed is drastically reduced and your turn capability improved. With any luck the attacker will not be able to slow down as quickly, and 'flies through', when full welly and nozzles forward puts you in the attacking seat. There was, of course, a high risk of a collision with the unsuspecting attacker when presented with a rapidly growing plan-form Harrier.

The last. party trick' which WAS fun (and I never did this below 10k) was to slow to about 220kts, and apply both full power, full down nozzle and back stick. The bonajet would neatly flip end over end at which point everything got put back in the proper place and you recovered from the ensuing dive.

Now we come to the down side. I remember one of many audiences at the feet of the venerable John Farley, who wisely cautioned "In a normal combat environment, when you are facing more than one threat, while the action is pretty to watch, remember with the loss of speed you then become an almost stationary target for the attacker's number two or 'x', or some missile flinging chap."

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Re: VTOL - Verbiage and Videos

#9 Post by TheGreenGoblin » Sun Mar 27, 2022 10:59 am

One just has to wait, and a viffer will come along and explain. Thanks for that very interesting post Boac.

Another enigma was explained to me by Richard Whittle in "The Dream Machine" yesterday. I had always wondered what had happened here.




Pilots Wilson and Freisner were doing the first test flight with Osprey number 5 when, almost immediately, on lift off from the pad, it began to run counter to Wilson's roll control inputs and the oscillations, both vertical, and then in all axes, quickly became divergent and the aircraft crashed and was destroyed in the ensuing fire. Both pilots escaped with minor cuts and bruises.

The board of enquiry found that the Osprey's fly by wire system had had two of three components called "vyros", an electronic gyroscopic that measures roll rate, that had been mis-wired, resulting in the 180 degree divergent behaviour. Wilson, primarily a helicopter test pilot admitted later to the author, that in retrospect, he believed that he might also have reverted to a helicopter pilot's muscle memory in the crisis and may have looked to raise the collective which, in the V-22, designed to be more compatible with a fixed wing aircraft, was akin to pulling back a throttle, thus decreasing power, as opposed to what it does in a helicopter where raising (pulling back) the collective results in an increase of power and pitch. Thus the aircraft became divergent in the vertical axis as well.

I have found myself doing similar silly things in non crisis situations, like using the top of the instrument console for a horizon reference, as opposed to the compass in the R44 resulting in poor attitude control.
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Re: VTOL - Verbiage and Videos

#10 Post by Boac » Sun Mar 27, 2022 1:19 pm

They were 'n' lucky not to die in that crash!!

I am struggling with the description of a 'collective' which reduces power when 'pulled up'. How on earth do you hover this thing?

I see from another source that the so-called 'collective' is actually a throttle and it appears to move backwards and forwards, not up and down. That makes more sense, ie go up push the 'throttle' forward, just like a Harrier. That certainly makes sense for forward flight, although how engine rpm and blade pitch are inter-related for hoovering I know not.

Any of our helo experts to comment?

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Re: VTOL - Verbiage and Videos

#11 Post by TheGreenGoblin » Sun Mar 27, 2022 3:11 pm

Boac wrote:
Sun Mar 27, 2022 1:19 pm
They were 'n' lucky not to die in that crash!!

I am struggling with the description of a 'collective' which reduces power when 'pulled up'. How on earth do you hover this thing?

I see from another source that the so-called 'collective' is actually a throttle and it appears to move backwards and forwards, not up and down. That makes more sense, ie go up push the 'throttle' forward, just like a Harrier. That certainly makes sense for forward flight, although how engine rpm and blade pitch are inter-related for hoovering I know not.

Any of our helo experts to comment?
The collective controls the pitch. Pull and the pitch increases. Push down and the pitch decreases. The throttle is a twist on the end of the collective lever. If you pull the collective up you need to twist the throttle anti clockwise to ensure the ERPM and thus RRPM is maintained as the pitch increases and the other way if you push down

On the R44 there is a correlator that kicks in as the manifold pressure, governed by the collective reaches about 18 inches MAP or 80% RPM and the throttle is then governed, to ensure the engine RPM is maintained in line with the collective position in order to maintain RRPM.
Correlator
• Correlator is a mechanical linkage from the Collective Lever to
the Engine, as the lever is raised the Correlator increases
Engine RPM and MAP.
• When the lever is lowered it reduces Engine RPM and MAP. It
is 95% effective, especially between 16” MAP and 23” MAP
• Below 16” MAP the Correlator OVER COMPENSATES
• Above 23” MAP the Correlator UNDER COMPENSATES
Governor
• The Governor is an electrical system that senses ERPM
changes and applies the necessary THROTTLE adjustment to
maintain the correct constant ERPM
• The Governor is only used to fine tune the ERPM that the
Correlator does not do and maintain a constant 102% ERPM.
• The Governor switch is located on the end of the
Collective. It should always be ON for flight (except in
case of training or actual failure).
• The aircraft must not be flown with an inoperable
Governor
• The Governor is only active above 80% RPM
Don't let the RRPM decay below 90% in flight. If you reach 80% you are probably deaf and soon will be as you will soon be dead if you don't do something about your decaying RRPM. Immediate collective push down is required to reduce the pitch.
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Re: VTOL - Verbiage and Videos

#12 Post by Boac » Sun Mar 27, 2022 4:09 pm

The collective controls the pitch. Pull and the pitch increases. Push down and the pitch decreases. The throttle is a twist on the end of the collective lever. If you pull the collective up you need to twist the throttle anti clockwise to ensure the ERPM and thus RRPM is maintained as the pitch increases and the other way if you push down
I'm actually familiar with that! I didn't realise the R44 was that simple with a sort of 'auto-throttle. :))

It appears, surely, that calling the thing on the Osprey a 'collective' is a misnomer?

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Re: VTOL - Verbiage and Videos

#13 Post by TheGreenGoblin » Sun Mar 27, 2022 4:31 pm

Boac wrote:
Sun Mar 27, 2022 4:09 pm
The collective controls the pitch. Pull and the pitch increases. Push down and the pitch decreases. The throttle is a twist on the end of the collective lever. If you pull the collective up you need to twist the throttle anti clockwise to ensure the ERPM and thus RRPM is maintained as the pitch increases and the other way if you push down
I'm actually familiar with that! I didn't realise the R44 was that simple with a sort of 'auto-throttle. :))

It appears, surely, that calling the thing on the Osprey a 'collective' is a misnomer?
Absolutely. In fact it was called something rude in honour of the Boeing manager who insisted it worked the way it did. I'll fish the story out and post it here when I get home.
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Re: VTOL - Verbiage and Videos

#14 Post by TheGreenGoblin » Sun Mar 27, 2022 8:08 pm

TheGreenGoblin wrote:
Sun Mar 27, 2022 4:31 pm
I'm actually familiar with that! I didn't realise the R44 was that simple with a sort of 'auto-throttle. :))

It appears, surely, that calling the thing on the Osprey a 'collective' is a misnomer?
Sorry, talk about teaching an ex Harrier pilot how to suck eggs. ;)))

I assume you might have done some helicopter time prior to flying that bird as well?
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Re: VTOL - Verbiage and Videos

#15 Post by Boac » Sun Mar 27, 2022 8:30 pm

10 hrs, all dual, Whirlwind, including engine offs and clearings. Excellent tuition. (My spot turns could, by the way, take several football pitches.... =)) )

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Re: VTOL - Verbiage and Videos

#16 Post by TheGreenGoblin » Sun Mar 27, 2022 8:53 pm

Boac wrote:
Sun Mar 27, 2022 8:30 pm
10 hrs, all dual, Whirlwind, including engine offs and clearings. Excellent tuition. (My spot turns could, by the way, take several football pitches.... =)) )
I suspected so, and even if not, you do understand pitch for God's sake... =))

By the way, my spot turns are now on the turn too as they say! :) ;)))

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Elusive."

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Re: VTOL - Verbiage and Videos

#17 Post by Boac » Sun Mar 27, 2022 9:09 pm

A cracking course at RAF Shawbury - no groundschool, no checks to learn, no tests, just pure poling. I actually suggested to their Airships that they might 'review' the traditional mind-numbing 6 weeks of g/s before you get your mitts on it, learning of checks, test test test etc. in view of the progress we were able to make in a relaxed and enjoyable environment - as you might expect, my paper went into the circular filing cabinet :))

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TheGreenGoblin
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Re: VTOL - Verbiage and Videos

#18 Post by TheGreenGoblin » Sun Mar 27, 2022 9:14 pm

Boac wrote:
Sun Mar 27, 2022 9:09 pm
A cracking course at RAF Shawbury - no groundschool, no checks to learn, no tests, just pure poling. I actually suggested to their Airships that they might 'review' the traditional mind-numbing 6 weeks of g/s before you get your mitts on it, learning of checks, test test test etc. in view of the progress we were able to make in a relaxed and enjoyable environment - as you might expect, my paper went into the circular filing cabinet :))
Toujours la meme.. :-s

Let natural skill and intelligence abide, and we will all be better off. :-bd

But we all need discipline...
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."

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Re: VTOL - Verbiage and Videos

#19 Post by TheGreenGoblin » Tue Mar 29, 2022 9:46 am

The first of the tiltrotors... the Transcendental Model 1-G <<far out man>>

Transcendental.JPG
Transcendental.JPG (30.5 KiB) Viewed 2240 times
The Transcendental Aircraft Company was founded in January 1947 at New Castle, Delaware by Mario Guerrieri and Bob Lichten, two employees of Kellet Aircraft, to develop the Model 1-G, on which they had begun design work in 1945. Their design was a small cantilever monoplane powered by a single 160 hp (120 kW) Lycoming O-290-A air-cooled flat-four engine positioned in the fuselage that drove two 3-blade rotors at the tips of the wings via a two-speed reduction gearbox. Two 1⁄6 hp (0.12 kW) electric motors were used to tilt the rotors, with the rotors linked by a shaft running through the wing to ensure that both rotors would be tilted at the same angle. A steel tube forward fuselage carried the single pilot, engine and gearbox, with the open cockpit positioned forward of the engine and gearbox. An aluminum alloy monocoque tail boom carried the aircraft's tail surfaces. A fixed tricycle landing gear was fitted.

The aircraft's rotors were controlled with cyclic and collective controls as used by a helicopter, for use in helicopter mode, while conventional ailerons, elevators and a rudder were fitted to the aircraft's wings and tail to control the aircraft in airplane mode

Development was slow owing to a shortage of funds, with the prototype sufficiently complete to allow testing on a ground test rig in 1951, although it was badly damaged later that year when the rotors disintegrated on the test bed during the first run at full revolutions. A series of contracts from the United States Air Force (USAF) allowed development to continue, and for the Model 1-G to be rebuilt into a form suitable for flight testing.

Lichten left Transcendental in 1948, and, in September 1952, Guerrieri sold his interests in the company to William E. Cobey Jr., a Kellett Aircraft Corporation vibrations expert who continued the development of the Model 1-G. With some funding provided by a 1952 Army/Air Force contract for flight data reports and analyses, hover testing of the 1750 lb. Model 1-G began on June 15, 1954. A second, improved, Transcendental tilt rotor aircraft, the 2,249 pounds (1,020 kg), two seat place Model 2, was subsequently developed by William E. Cobey Jr. but funding limitations resulting from the withdrawal of Air Force support prevented the expansion of the flight envelope, and the program was terminated in 1957.
Transcendental Model 1-G
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."

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Re: VTOL - Verbiage and Videos

#20 Post by TheGreenGoblin » Tue Mar 29, 2022 10:23 am

Bob Lichten went on work on the Bell XV-3 noted in an earlier post. The XV-3 is really the granddaddy of the current V-22 Osprey...

Bell XV-3.JPG
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."

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