Ernie P.

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I don't know how much more you can reveal, Top_Gunn. I would have thought (4), (9) and (12) would do it. Maybe his eye? Thanks; Ernie P.

wingspar

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Gabriele D'Annunzio

Dave N

Top_Gunn

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D'Annunzio it is, and you're up, Dave. The mission mentioned in clue 2. was a raid on a harbor shortly after the Italian army's retreat from Caporetto. The leaflet dropping was on Vienna, a mission on which nine planes made a 700 mile round trip, an impressive feat in those days. D'Annunzio not only led the raid, he wrote the leaflets. He was born in 1863, and so was in his 50s when World War I began. Quite an unusual biography for a fighter pilot.

wingspar

My Feedback: (3)

And a simple name the plane.......

Ernie P.

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This won't last long, I think. I was good last time. (-: Thanks; Ernie P.

Ernie P.

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Martin XB-51. Thanks; Ernie P.


The Martin XB-51 was an American "tri-jet" ground attack aircraft designed to a 1945 United States Army Air Forces requirement. It was originally designed as an attack aircraft by the Air Force under specification V-8237-1 and was designated XA-45. The "A" ground attack classification was eliminated the next year, and the XB-51 designation was assigned instead. The requirement was for low-level bombing and close support.

The XB-51 lost out in evaluation to the English Electric Canberra which entered service as the B-57.

The resulting unorthodox design, first flying on 28 October 1949, was (unusually for a combat aircraft) fitted with three engines, General Electric J47s in this case: one at the extreme tail with an intake at the base of the tailfin, and two underneath the forward fuselage in pods. The innovative, variable incidence wings, swept at 35° and with 6° anhedral, were equipped with leading-edge slats, full-width flaps and spoilers instead of ailerons. The combination of variable incidence adjustment and slotted flaps allowed for a shorter takeoff run. Four 954 lb (4.24 kN) thrust Rocket-Assisted Take Off (RATO) bottles with a 14-second burn duration could be fitted to the rear fuselage to improve takeoff performance. Spectacular launches were a feature of later test flights.

The main landing gear consisted of dual sets of wheels in tandem in the fuselage, similar to the B-47 Stratojet, with outrigger wheels at the wingtips (originally proved on a modified B-26 Marauder named "Middle River Stump Jumper"). The B-51 was a large but aerodynamically "clean" design which incorporated nearly all major systems internally. The aircraft was fitted with a rotating bomb bay, a Martin trademark; bombs could also be carried externally up to a maximum load of 10,400 lb (4,700 kg), although the specified basic mission only required a 4,000 lb (1,814 kg) bombload. Eight 20 mm (.79 in) cannons mounted in the nose would have been installed in production aircraft.

Crew provision was for a pilot under a "fighter"-type bubble canopy and a SHORAN (short-range navigation and bombing system) operator/navigator in a compartment located lower than and to the rear of the cockpit (only a small observation window was provided). Both crew members were provided with a pressurized, air-conditioned environment, equipped with upward-firing ejection seats. The XB-51 was the first Martin aircraft equipped with ejection seats; the ejection seats being of their own design.


In 1950, the United States Air Force issued a new requirement based on early Korean war experience for a night intruder/bomber to replace the A-26 Invader. The XB-51 was entered, as well as the Avro Canada CF-100 and the English Electric Canberra. The Canberra and XB-51 emerged as the favorites. The XB-51 was a highly maneuverable aircraft at low level, and substantially faster than the Canberra (its "turn-of-speed" was faster than most fighter aircraft of the era). However, its load limiting factor of only 3.67 g (36 m/s2) restricted tight turns, and the XB-51's endurance was substantially poorer than the Canberra's; this latter proved to be the deciding factor. Additionally, the tandem main gear plus outriggers of the XB-51 was thought unsuitable for the requirement to fly from emergency forward airfields.

The Canberra was selected for procurement and the XB-51 program ended. Martin did not end up the loser, however, for they were selected to build the 250 Canberras ordered under the designation B-57A. Furthermore, the rotating bomb bay was incorporated in the B-57. A proposed B-57 Super-Canberra also included XB-51 features, such as swept wing and tailplane. In the end it was never built, mainly because it was a new design and would have taken too long to put in production, although it promised much better speed and performance.

Flight testing for research purposes continued after program cancellation. The second prototype, 46-686, which first flew in 1950, crashed on 9 May 1952 during low-level aerobatics. The first prototype, 46-685 continued to fly, including appearing in the film Toward the Unknown as the "Gilbert XF-120" fighter. The surviving prototype was en route to Eglin AFB to shoot additional footage when it crashed during takeoff following a refueling stop in El Paso, Texas, on 25 March 1956.

wingspar

My Feedback: (3)

You are correct :-)

Ernie P.

My Feedback: (3)

Thank you, Sir. I did try to be nice. I am very nice; just very weak. <G> I hope you all enjoy this next question. It's a common device; smaller than a breadbox; found around the home. Thanks; Ernie P.


Question: What warbird enhancing invention do I describe?

Clues:

(1) This device was perhaps most useful when installed on combat aircraft.

(2) However, it was also very useful when installed on combat ships.

(3) And, very useful when utilized by land combat units of all sorts.

JohnnyS

Cavity magnetron?

uncljoe

My Feedback: (8)

IFF transmitter/receiver
Semper Fi

JohnnyS

Sir, If the IFF Transmitter/Receiver" is "a common device; smaller than a breadbox; found around the home" then you live in a TOUGH neighbourhood!

uncljoe

My Feedback: (8)

I'm still trying to figure out what a BREADBOX is.........

Ernie P.

My Feedback: (3)

Well..... THAT didn't take long. Very good, JohnnyS; and you are up, Sir. I was really going for the Anode Block; but you're close enough. The cavity magnetron made possible higher frequency (shorter wave length) radar, which lead to the allies gaining a huge lead in radar effectiveness; and the microwave oven. Several BILLION have been produced. Thanks; Ernie P.


Question: What warbird enhancing invention do I describe?

Clues:

(1) This device was perhaps most useful when installed on combat aircraft.

(2) However, it was also very useful when installed on combat ships.

(3) And, very useful when utilized by land combat units of all sorts.

(4) And some ancillary uses were discovered which resulted in an incredible number of these devices being manufactured.

(5) Even today, they are ubiquitous.

(6) First developed (invented?) in an “enemy” country, pre-WWII. However, it was not considered to be “useful”.

(7) Then improved and adapted in a friendly country. However, they didn’t have the money and resources necessary to fully develop this “new” version.

(8) So, they brought it to the United States, and asked them to develop and manufacture the device; and to allow them to use it.

(9) Many people believe this single device was a “war winning” tool.

(10) It made allied aircraft, ships and ground units (eventually, both military and civilian) much more effective.

(11) It also made all our lives both safer and more convenient.

Answer: The Anode Block of the Cavity Magnetron; which made possible advanced radar sets in WWII.




The cavity magnetron is a high-powered vacuum tube that generates microwaves using the interaction of a stream of electrons with a magnetic field while moving past a series of open cavities. Electrons passing by the openings to the cavities cause the interior to fill with a radio signal, and by sizing the cavity appropriately, the signal will resonate at a selected frequency and cause a powerful signal to be generated. Unlike other tubed-based microwave devices, namely the klystron and traveling-wave tube (TWT), the magnetron is not an amplifier of an existing signal, it produces a microwave signal directly due to its internal physical arrangement.

The first form of magnetron tube, the split-anode magnetron, was invented by Albert Hull in 1920, but it wasn't capable of high frequencies and was little used. Similar devices were experimented with by many teams through the 1920s and 30s. The modern 'resonant' cavity magnetron tube was invented by John Randall and Harry Boot in 1940 at the University of Birmingham, England. The high power of pulses from their device made centimeter-band radar practical, with shorter wavelength radars allowing detection of smaller objects from smaller antennas. The compact cavity magnetron tube drastically reduced the size of radar sets so that they could be installed in anti-submarine aircraft and escort ships.

In the post-war era the magnetron became less widely used in the radar role. This was due to the fact that the magnetron's output changes from pulse to pulse, both in frequency and phase. This makes the signal unsuitable for pulse-to-pulse comparisons, which is widely used for detecting and removing "clutter" from the radar display. The magnetron remains in use in some radars, but has become much more common as a low-cost microwave source for microwave ovens. In this form, approximately one billion magnetrons are in use today.


The first simple, two-pole magnetron was developed in 1920 by Albert Hull at General Electric's Research Laboratories (Schenectady, New York), as an outgrowth of his work on the magnetic control of vacuum tubes in an attempt to work around the patents held by Lee De Forest on electrostatic control.

Hull's magnetron was not originally intended to generate VHF (very-high-frequency) electromagnetic waves. However, in 1924, Czech physicist August Žαček (1886–1961) and German physicist Erich Habann (1892–1968) independently discovered that the magnetron could generate waves of 100 megahertz to 1 gigahertz. Žαček, a professor at Prague's Charles University, published first; however, he published in a journal with a small circulation and thus attracted little attention. Habann, a student at the University of Jena, investigated the magnetron for his doctoral dissertation of 1924. Throughout the 1920s, Hull and other researchers around the world worked to develop the magnetron. Most of these early magnetrons were glass vacuum tubes with multiple anodes. However, the two-pole magnetron, also known as a split-anode magnetron, had relatively low efficiency. The cavity version (properly referred to as a resonant-cavity magnetron) proved to be far more useful. In 1937-1940 a multi-cavity magnetron was built by the British physicist John Randall, together with a team of British coworkers, for the British and American military radar installations in World War II.

While radar was being developed during World War II, there arose an urgent need for a high-power microwave generator that worked at shorter wavelengths (around 10 cm (3 GHz)) rather than the 150 cm (200 MHz) that was available from tube-based generators of the time. It was known that a multi-cavity resonant magnetron had been developed and patented in 1935 by Hans Hollmann in Berlin. However, the German military considered the frequency drift of Hollman's device to be undesirable, and based their radar systems on the klystron instead. But klystrons could not at that time achieve the high power output that magnetrons eventually reached. This was one reason that German night fighter radars were not a match for their British counterparts.


The anode block which is part of the cavity magnetron developed by John Randall and Harry Boot in 1940 at the University of Birmingham.

In 1940, at the University of Birmingham in the United Kingdom, John Randall and Harry Boot produced a working prototype similar to Hollman's cavity magnetron, but added liquid cooling and a stronger cavity. Randall and Boot soon managed to increase its power output 100 fold. Instead of abandoning the magnetron due to its frequency instability, they sampled the output signal and synchronized their receiver to whatever frequency was actually being generated. In 1941, the problem of frequency instability was solved by coupling ("strapping") alternate cavities within the magnetron. (For an overview of early magnetron designs, including that of Boot and Randall, see)

Because France had just fallen to the Nazis and Britain had no money to develop the magnetron on a massive scale, Churchill agreed that Sir Henry Tizard should offer the magnetron to the Americans in exchange for their financial and industrial help (the Tizard Mission). An early 6 kW version, built in England by the General Electric Company Research Laboratories, Wembley, London (not to be confused with the similarly named American company General Electric), was given to the US government in September 1940. At the time the most powerful equivalent microwave producer available in the US (a klystron) had a power of only ten watts. The cavity magnetron was widely used during World War II in microwave radar equipment and is often credited with giving Allied radar a considerable performance advantage over German and Japanese radars, thus directly influencing the outcome of the war. It was later described by America as "the most valuable cargo ever brought to our shores".

The Bell Telephone Laboratories made a producible version from the magnetron delivered to America by the Tizard Mission, and before the end of 1940, the Radiation Laboratory had been set up on the campus of the Massachusetts Institute of Technology to develop various types of radar using the magnetron. By early 1941, portable centimetric airborne radars were being tested in American and British aircraft. In late 1941, the Telecommunications Research Establishment in Great Britain used the magnetron to develop a revolutionary airborne, ground-mapping radar codenamed H2S. The H2S radar was in part developed by Alan Blumlein and Bernard Lovell.

Centimetric radar, made possible by the cavity magnetron, allowed for the detection of much smaller objects and the use of much smaller antennas. The combination of small-cavity magnetrons, small antennas, and high resolution allowed small, high quality radars to be installed in aircraft. They could be used by maritime patrol aircraft to detect objects as small as a submarine periscope, which allowed aircraft to attack and destroy submerged submarines which had previously been undetectable from the air. Centimetric contour mapping radars like H2S improved the accuracy of Allied bombers used in the strategic bombing campaign. Centimetric gun-laying radars were likewise far more accurate than the older technology. They made the big-gunned Allied battleships more deadly and, along with the newly developed proximity fuze, made anti-aircraft guns much more dangerous to attacking aircraft. The two coupled together and used by anti-aircraft batteries, placed along the flight path of German V-1 flying bombs on their way to London, are credited with destroying many of the flying bombs before they reached their target.

Since then, many millions of cavity magnetrons have been manufactured; while some have been for radar the vast majority have been for microwave ovens. The use in radar itself has dwindled to some extent, as more accurate signals have generally been needed and developers have moved to klystron and traveling-wave tube systems for these needs.

JohnnyS

Well foo. I didn't expect to win that one. OK, let's try a new one:

1. Almost 200 were built, but only one example had retractable landing gear.

2. Twin engine monoplane.

4. Designed for reconnaissance but could carry bombs for anti-submarine attacks.

JohnnyS

1. Almost 200 were built, but only one example had retractable landing gear.

2. Twin engine monoplane.

3. Designed for reconnaissance but could carry bombs for anti-submarine attacks.

4. When carrying bombs, the bombs were not carried internally: They were in a "gondola" attached beneath the fuselage.

JohnnyS

1. Almost 200 were built, but only one example had retractable landing gear.

2. Twin engine monoplane.

3. Designed for reconnaissance but could carry bombs for anti-submarine attacks.

4. When carrying bombs, the bombs were not carried internally: They were in a "gondola" attached beneath the fuselage.

5. Flew for one nation and both sides.

SimonCraig1

The Amiot 143?

JohnnyS

Not the Amiot, no.

1. Almost 200 were built, but only one example had retractable landing gear.

2. Twin engine monoplane.

3. Designed for reconnaissance but could carry bombs for anti-submarine attacks.

4. When carrying bombs, the bombs were not carried internally: They were in a "gondola" attached beneath the fuselage.

5. Flew for one nation and both sides.

6. At the end of the war the aircraft were used for liaison duties around the Mediterranean carrying up to four passengers.

RCKen

My Feedback: (9)

Fiat RS.14???

MJD

My Feedback: (1)

A question close to my heart, but I missed it as I wasn't paying attention. My dad was a squadron leader with Pathfinders and heavily involved in radar R&D as it was his field of expertise. I might have got one finally!

Ernie P.

My Feedback: (3)

Why do I think you play this game better than you want us to think? But, yes; that would probably have been an easy one for you. Thanks; Ernie P.

JohnnyS

RCKen,

You have it, sir. Well done! Over to you.

Ernie P.

My Feedback: (3)

RCKen; time for a question, Sir. Thanks; Ernie P.

RCKen

My Feedback: (9)

I need to get back down to my office and get the next question off of the thumb drive I left laying on my desk. Either that or I need to make up the quiz again. Either way, I'll have it a bit later this morning. sorry for the delay guys.

Ken

RCKen

My Feedback: (9)

Ernie,
can you bail me out here?? I thought that I was really great quiz all ready for you guy this time, but as I looked at it all the questions started to look really familiar, and then I realized that I had already posted quiz before. So I'm stuck with nothing ready to go. If you all want to wait I an make a up a new quiz tonight and start posting it in the morning. I'm hoping you guys will wait till the morning and give a chance to get going with another plane, but if you want to pass this on the Ernie or somebody else I would totally understand that. I do apologize to the group for the problem

That brings up a question that comes to my mind as Forum Manager here at RCU. Is there anybody here keeping track of what's going on where in the forum?? This thread is a great group of guys and doesn't need any policing so that's not an issue and that's not what I'm saying here. but what I'm saying is just more keeping track of what questions have been asked in the contest and such. If there is somebody that want's to step and be the Moderator for this thread thread here so that they can help keep this contest running a bit better I would be more than happy to promote you to that position!!!

On thing that comes to mind if we promote somebody a position like that is that they could keep a collection of questions ready to so that situations like what I had come up they would be ready to step in and post something. Anyway, something to think about.

Anyway, let me know if Ernie or somebody else has something ready to go to bail it out.

Ken