Airborne Awesomosity

Bearing Down: A Return to the Cold War?

During the Cold War, America’s air defense network could count on a few things. First, that they would see Soviet aircraft flying on the very edge of our airspace. Second, those aircraft would be the Tupolev Tu-95 Bear or one of its variants. Once the Soviet Union fell in the early 1990s, these flybys started to dwindle. In fact, by 2009 the US was considering an incursion by Russian aircraft something strange; not routine. However, as Russia seeks to re-enter the superpower club, it has been doing a little saber rattling lately. Over the last few years, the US and Europe have been reporting more and more incursions of Russian aircraft over our northern borders. That aircraft is the same as its ever been, the Tupolev Tu-95 Bear.

The Tu-95/1 was the first prototype of this storied and fearsome family of strategic aircraft. It appeared in 1952 as a result of a 1950 requirement for a new bomber that could carry 11,000 kg of nuclear death to a target 8,000 km away. Just prior to this, Tupolev had tried to scale up a Tu-4 (the Soviet copy of the Boeing B-29 Superfortress) to perform a similar mission, but found the huge aircraft was sorely underpowered by piston engines. Tupolev then turned to the new-fangled jet engine, but decided the available AM-3 jet engines would be so fuel hungry the range would be impossible to meet. Thus, a compromise was struck — turboprop engines with huge contra-rotating propellers that don’t so much as pull the aircraft through the air as they do beat the atmosphere back allowing the slender fuselage and swept wings to progress unimpeded. This is, of course, an incredibly brutal method of propulsion for such a large aircraft, and the Bear is known as the loudest aircraft on earth.

After flying six months, Tu-95/1 crashed after a gearbox failure in one of its four Kusnetsov 2TV-2F coupled turboprop assemblies. Tu-95/2 arrived with a more reliable gearbox assembly and completed the remaining flight test program. By January 1956, the Tu-95 was approved for production and it was free to torture the guys at Offutt AFB.

The first production units, Tu-95M, were purely bombers and would patrol over North America and Europe ready to drop it’s load of bombs should the capitalist imperialist dogs even so much as twitch over the nuclear launch buttons. Later variants would be fitted for in-flight refueling, air-ground missiles, and — most famously — for ASW operations and maritime reconnaissance. These are the Bears that gave NATO forces the most grief, and are the ones still flying today.

The Tu-95 and its variants are expected to stay flying well into the middle of this century. That would give it a longevity only rivaled by the Boeing B-52.

[Image Credit: Public Domain]

  • Number_Six

    Three cheers for the Soviets enabling head-assplodingly awesome juxtapositions like these:
    <img src="http://www.acig.org/artman/uploads/bh01.jpg&quot; width="500" />
    <img src="http://i.imgur.com/zwcrw.jpg&quot; width="500" />

  • The Professor

    Is that a refueling probe jutting out of the nose or some weird weapon?
    I've wondered about the counter-rotating props that the Soviets seemed to be so fond of, and just how well they actually worked. Do they actually provide that much more thrust?

    • Number_Six

      Some quick and dirty reasons cribbed off das interboots but accurate as I recall from past readings:

      It removes the swirl from the prop-wash, this increases the percentage of the work performed on the flow that can be used for thrust.

      It allows a greater effective pressure rise across the entire prop disk. This is similar to a multi-stage compressor. Since the pressure rise lasts only as long as the flow takes to get through the disk it is relatively immeasurable. However, the flow speed is measurable. This produces greater thrust from a smaller diameter prop.

      It allows the prop to turn at a speed closer to that of the gas turbine, decreasing gearbox size and weight.

      Reduced torque effects.

      • Number_Six

        They must have worked because the Bear was the fastest propellor-driven aircraft in history. There were plenty of aircraft with this propellor arrangement but they tend to be fairly obscure, like the Fairey Gannet ASW aircraft and the later powerful Spitfires, like this XIX:
        <img src="http://www.aviatormodteam.xtreemhost.com/main/images/aircraft/spitfire19_real.jpg&quot; width="500" />

        • CaptianNemo2001

          The XF-12 (XR-12) "Rainbow" was going to be fitted with counter-rotating propellers but they suffered from gear box failure and rather then replace and redesign the gearbox they said "screw it" and slapped on more normal propellers. The XF-11 also had some counter-rotating but yet again the gear issues caused O' Howard to crash and burn…

          The "Bear" was such a clean aircraft then they started adding all sorts of crap to it.

          While we are at it please do not forget the Tupolev Tu-114, The Republic XF-84H "Thunderscreech", MC-72, and the XF-88B. That should keep people busy for now…

          • fodder650

            Didn't I cover the Thunderscreech as part of my F-84 article? That aircraft caused the ground crews to get nausea because the propeller tips broke the sound barrier.

            As for the Bear losing its clean look. When you have an aircraft in service for that longer you just keep attaching stuff to it to modernize it. A good example in the US is the C-130. Here is what the prototypes looked like.

            <img src="http://upload.wikimedia.org/wikipedia/commons/9/9b/YC-130s_formation_usaf.jpg&quot; width=600 />

          • CaptianNemo2001

            But the C-130 ACTUALLY looks better now with the dome slapped on the front of it then without.

            Also the tips on the Bear also break the sound barrier at Mach 1.16 I believe and the XF-84H's tips do Mach 1.18.

      • The Professor

        Thanks for the info. It sounds complicated.

      • Tiller188

        Makes sense. I always figured they must be pretty effective based on the fact that someone went to the trouble of adding them to a P-51 to make the air racer, Precious Metal.

        They also look really mesmerizing at startup.
        http://www.youtube.com/watch?v=HVWmI1PMUUs&fe

        [sorry for threadjack]

    • fodder650

      Six is correct in what he said but there are a couple more factors. First it eliminates the torque effect of the props. Which is a major issue when each one is pushing 5000 horsepower or so. Add in that, like in a boat, a propeller designs to work with that much horsepower would be huge and unwieldy. This allows you to double the effective propeller area without all the height to go with it.

      Like six was saying an awful lot of aircraft were designed with this in mind towards the end of the war but never went into production that way. It was just to complex. Of course its making a comeback in an odd way. Several of the major aircraft manufacturers are thinking of bringing it back as a way to increase the efficiency of the jet engine.

      <img src="http://history.nasa.gov/SP-4219/4219-322.jpg&quot; width=600 />

      • CaptianNemo2001

        Even with halving the area the props on the Bear are massive…

  • Miguel Vargas-Caba

    Hello! As a self-made expert on the TU-95 Bears (one book under my belt, a second one in the works), I'd like to show you several photos from my forthcoming book: "Chronicles of the Bear – Stories from the Annals of the Cold War". It shows that not only we took photos of the Bears, but similarly, they took photos of us! More photos like these will be in the book.

    Also, I'm attaching a photo with a man standing by the massive 18.5 ft (5.6m) AV-24 propellers of the Kuznyetsov NK-12 engine, to give a size reference. As Fodder650 correctly points out, if they did not use counter-rotating propellers, the equivalent would have been more than enormous 39 ft (11m) long propellers, obviously unwieldy. These engines were and are used not only in the TU-95 and the TU-114, but also in the TU-126 "Soviet AWACS" (NATO: Moss), the An-22 "Antey" (NATO: Cock), the TU-142 (Bear F) ASW airplane, and even in the "Zubr" (Bison) hovercraft!

    PROFESSOR: On the nose the TU-95 and the TU-142 carry a "Konus" in-flight refueling system probe 10 ft (2.5m) long. As far as weapons is concerned, they carry only defensive weapons in the form of two AM-23 23mm cannons in the tail.

  • Pingback: Bears in the Air : Atomic Toasters()

-->