K777 and Bluebird

Discussion in 'Boat Design' started by FranklinRatliff, Nov 4, 2011.

  1. FranklinRatliff

    FranklinRatliff Previous Member

    http://www.youtube.com/watch?v=g0aDB4Rdlzc

    Bluebird sank at Lake Mead in 1955. Which is not surprising considering during NORMAL operation in 1955 (as shown in the above film) Bluebird was almost a submarine anyway. And K777 isn't Bluebird. It has an aluminum instead of steel frame, which not only lightens the boat but shifts the center of gravity. And it has a fixed fin where Bluebird had a retractable water brake, creating a nose down moment different from Bluebird. The punters who were expecting the K777 team to just roll the boat down the slipway and already have the fore and aft trim correct when it hit the water were just fooling themselves.
     
  2. Blowtorch
    Joined: Nov 2011
    Posts: 5
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: USA

    Blowtorch Junior Member

    K777

    I suggest that you take another look at a picture of the K777 stern.
    You will find that the waterbrake is in the center, rudder on left side and fin on the right side, just as it is on the real Bluebird.
     
  3. FranklinRatliff

    FranklinRatliff Previous Member

    Bluebird had no fixed fin on the stern and the water brake was on the starboard side.
     
  4. Blowtorch
    Joined: Nov 2011
    Posts: 5
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: USA

    Blowtorch Junior Member

    Wrong again, Franklin.
    The fin on the stern of Bluebird, was to compensate for rudder drag.
     

    Attached Files:

  5. FranklinRatliff

    FranklinRatliff Previous Member

    My mistake. Thanks for the photo.

    However, the fixed fin was a later addition to Bluebird and not part of the original design.

    People who look down their noses at K777 should remember there aren't a whole lot of workable jet hydroplane designs out there, so if your goal is to set a water speed record a very sensible option is adopting the Bluebird design.

    http://www.lesliefield.com/personalities/les_staudacher_more_power_to_you.htm

    "Les Staudacher is the only man in the U.S. who has designed, built and driven a jet-powered boat. He had considerable driving hours with Tempo Alcoa before she blew up this June .while being tested with remote radio control. His experience with that craft resulted in the following observations Les recently made to me:
    "The greatest problem in designing a jet boat is getting around the wave-making resistance at low speed. This factor, that has presented little problem in most hydroplane designs, gives you fits with a jet job both while accelerating through the 'displacement boat' speed range and decelerating through it. Whatever configuration you use must be so designed that it throws no spray upward. Flying water is sucked into the jet intake with disastrous results.
    "So far our attempts to produce a hull form that minimizes wave-making resistance, to allow us to get on a plane, have been aerodynamically poor at high speeds. Their bottom air lift area tends to 'stall' at high speeds, resulting in an abrupt shift in behavior.
    "This business of getting on a plane is especially tough with a jet because-despite the high thrust rating of the engine-it seems that, at low boat speed, a good outboard could tow the jet rig backwards while the jet engine was wide open.
    "All that counts at high speed is the aerodynamic factor. Our tests have shown that aerodynamic problems are simple compared with the wave-making bit. From what we know, the 4,000 to 5,000 pounds of thrust developed by far-from current jet engines should easily give us a boat speed of 500 m.p.h."
    For those of the fraternity who have visualized jets powering everything from unlimited hydros to the smallest classes intended for youngsters, Staudacher has some disturbing views. Based on his experience lie can not foresee jets being used in any kind of competition. Here are his reasons.
    "I found .it was almost impossible to steer the boat until she had attained a good planing speed. After the headache of overcoming wave-making resistance the boat would 'break loose' and behave well around 50 m.p.h. Then, about 80, she would bog down to the point that the sponsons tended to bury and the tunnel bottom was riding on the water. To get through this phase, the jet engine had to be opened up wide. After a bit of this full power, the boat would break loose again and accelerate from 80 to 200 m.p.h. in six seconds. Better you should have her aimed right when she enters this stage! All of this adds up to the fact that there isn't enough room on the average race course to get a fleet of jets going and under control.
    "Tempo Alcoa threw a low but very wide rooster tail. There was so much water thrown out over such a wide area that passing her on a race course would be a virtual impossibility.
    "You mentioned that you thought a jet would be the best hope of the U.S. in regaining the Harmsworth Trophy. Please remember that a jet engine consumes 1,000 gallons of fuel each hour. A boat carrying enough fuel to get through a 45-mile Harmsworth race would be so overloaded that she would not be able to develop any real high speed.
    "When Tempo Alcoa was running at speeds above 200, it required real mileage to stop her. After cutting off the power on calm water she would travel a good half-mile before coming to a stop. If there was a chop, it took three to four times that distance to bring her to a halt. This would be too dangerous in competition. It was just this that made me run up on that peninsula out at Pyramid Lake last fall. I could see the thing in front of me but couldn't steer away from it and couldn't stop."
    (Reprinted from "More Power to You" by Mel Crook, Yachting, November 1960, pp.87-88)
     
  6. FranklinRatliff

    FranklinRatliff Previous Member

  7. FranklinRatliff

    FranklinRatliff Previous Member

    270 mph "Liquid Quicker" drag boat. For those who think the Bluebird design is just an historic relic and not so far ahead of its time it still remains relevant and contemporary.
     

    Attached Files:

  8. Loosecannon
    Joined: Dec 2008
    Posts: 20
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Australia

    Loosecannon Junior Member

    Yeah Bluebird was an amazing design, ... good for 200-250 and for it's era, but that was it, real pig to get on the plan intakes get water in them, and bad on ANY water with a ripple,.....and killed it's driver in the end due to being pushed beyond it's design limits , the outrigger comparison with Bluebird and new drag boats??.... well the outline shape and outriggers is where the similarity ends :D:D:eek:
     
  9. FranklinRatliff

    FranklinRatliff Previous Member

    What fundamental quantum leap in hydroplane design has occurred since Bluebird was built?

    Probably nothing wrong with the Bluebird design that couldn't be fixed with some CFD or more wind tunnel work.

    Who cares it's a pig to get on plane? It's for the water speed record not drag racing.
     
  10. Loosecannon
    Joined: Dec 2008
    Posts: 20
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Australia

    Loosecannon Junior Member

    Who said there was a Quantum leap in design.......... I would rather rather have a more proven, stable design, what lifts bluebird out of the water ( sponson design) kills it at high speed, A boat needs to handle a ripple, or small amount bad water, wind etc, considering you are running over 10-11 miles much hard to control than 400 meters.. other designs can handle that, bluebird didn't like it at all, you can wind tunnel all day long, how can that simulate water that is moving and rolling around, with lumps and hollow's etc, etc, Wind Tunnels helps to a certain degree, practical boat racing experience IS the part nearly all water speed record guy's are missing

    Who cares if it's a pig to plane??...... I think the guy's with K777 just found out, with a boat underwater right?
     
  11. Jimboat
    Joined: Feb 2002
    Posts: 237
    Likes: 10, Points: 18, Legacy Rep: 130
    Location: Canada

    Jimboat Senior Member

    The Bluebird's accomplishments were amazing for the times! High performance boat design has come a long way since the Bluebird first ran. There are engineering methods that can do a good job to predict and simulate performance of any hull design. That said, hull design is always a compromise of performance characteristics under different operating conditions and throughout the operating velocity range. There are only a few hull design & setup characteristics that can be adjusted while underway or during different operating conditions - the rest of the hull design/setup is 'fixed', hence the best compromise to achieve best results at optimum design operating condition while still getting satisfactory performance in off-peak conditions. So it should be no surprise that handling can be reduced at lower velocities, and particularly prior to reaching planing velocity. (I am sure that these characteristics were not unexpected to the K777 designers).
     
  12. FranklinRatliff

    FranklinRatliff Previous Member

    One thing that could be done with K777 is take advantage of the fact it is a jet. A thrust deflector plate could be installed in the exhaust stream that would load the stern and take weight off the bow while the boat is getting on plane then return to a neutral position once the boat is out of the water.
     
  13. FranklinRatliff

    FranklinRatliff Previous Member

    Campbell set seven water speed records with Bluebird. As early as 1957, he had made a one-way run of 286 mph.
     
  14. Loosecannon
    Joined: Dec 2008
    Posts: 20
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Australia

    Loosecannon Junior Member

    Bluebird was an amazing boat in it's day, no doubt, I am sure the guy's with K777 knew how it would handle off plane, and in the transition phase to planing, Sadly this is a difficult area for that design
     

  15. Loosecannon
    Joined: Dec 2008
    Posts: 20
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Australia

    Loosecannon Junior Member

    He sure did, with the best of British engineering of the day .....then Ken Warby built a boat in his backyard (on Campbells drinking budget )and ran 2 world records driving thru every world record Campbell done, in a boat he designed, built and drove ( the only person to ever do so), plus broke the record by the biggest margin in history,, first over 300MPH, and 500KMH, plus the boat looked great on smooth or rough water, 34 years later, still at the top of the tree, the only person alive to ever hold a unlimited water speed record :D
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.