Page 2 of 5 FirstFirst 1234 ... LastLast
Results 11 to 20 of 43

Thread: RV or Harmon Rocket for Competition?

  1. #11
    RetroAcro's Avatar
    Join Date
    Jul 2011
    Location
    Cary, NC
    Posts
    105
    Quote Originally Posted by steveinindy View Post
    Unless you can pass the military pilot physical exams and other tests (such as a stress echo), you really can't say you have that good of cardio for high G, etc. There are a lot of people whose first indication of severe cardiac problems that have likely existed for some time is a collapse and sudden death. I enjoy unusual attitudes too but there's a big difference between a few loops and spins and trying to sustain consciousness in a 7-9 g turn. The best advice I can offer- and this was given to me by a famous test pilot- was to always remember that the "squishy mass in the pilot's seat" is the weakest link in any aircraft. Just because an aircraft is tested to withstand aerobatic category maneuvers does not mean it's a good idea for the average Joe Q. Pilot to try to push that aircraft anywhere near those limits.
    I don't think he's looking to fly military fighters. Nobody sustains 7-9G in any piston plane, aerobatics or not. The Unlimited monoplanes might pull G is this range, but it'll only last about 1 second. There's no need to pull more than about 4.5G at the Sportsman level. And even at that, the G is experienced for very short amounts of time. You really don't have to be in great shape to fly aerobatics, or even competition acro. If you came to a contest you might be surprised that many guys have the same beer guts that non-acro guys have. :-)

    Quote Originally Posted by steveinindy View Post
    Then I would recommend against the RV series. They are good for basic stuff but I wouldn't want to try to pretend to be Maverick and Goose in one.
    I would recommend an RV. They are designed and stressed for aerobatics (+6/-3G) just like any other aerobatic airplane. My Pitts has the same stress limits. They are perfectly suitable for flying Primary and Sportsman level competition acro. Any airplane has its limitations. You would not subject an RV to the same stress and certain maneuvers that are possible in the carbon fiber monoplanes, but neither would you most other aerobatic airplanes that are not carbon monoplanes. I flew aerobatics for 5 years in an RV, and did all the aerobatics you can do in an airplane without inverted systems. Great airplane.

  2. #12
    steveinindy's Avatar
    Join Date
    Jul 2011
    Location
    Indiana
    Posts
    1,449
    I don't think he's looking to fly military fighters. Nobody sustains 7-9G in any piston plane, aerobatics or not. The Unlimited monoplanes might pull G is this range, but it'll only last about 1 second. There's no need to pull more than about 4.5G at the Sportsman level. And even at that, the G is experienced for very short amounts of time. You really don't have to be in great shape to fly aerobatics, or even competition acro. If you came to a contest you might be surprised that many guys have the same beer guts that non-acro guys have. :-)
    Oh, I know. I know a lot of military pilots who are rather flabby too. The point is not the actual level of fitness but the cardiac issues that tend to lurk asymptomatically in those of us with a sedentary lifestyle. I agree that there's no need to pull more than 4.5 g but would say that it extends beyond the sportsman level to include any level to be quite honest unless you're in combat. You get much beyond 5 or 6 g, especially if you're inverted and most people are going to find it downright unpleasant. Even with my masochistic streak, this is the case with me and with most of the folks I know who do aerobatics. I just don't see the need to do anything beyond that but then again, I tend to look at aerobatics and such at airshows like Oshkosh with a healthy degree of "Eh...that's nice....moving on". My point about the RV series being unsuited was from the assumption that he had little background in aerobatics and was looking to go out and really tear it up. Even for 4.5 g, a marginal factor of safety of 25% would put the RV series at the lower end of the suitability spectrum and I wouldn't go beyond that level in an aircraft without a much higher design load tolerance.
    Unfortunately in science what you believe is irrelevant.

    "I'm an old-fashioned Southern Gentleman. Which means I can be a cast-iron son-of-a-***** when I want to be."- Robert A. Heinlein.



  3. #13

    Join Date
    Oct 2011
    Location
    New Hampshire
    Posts
    985
    They information and opinion presented in the last post suggests an incomplete understanding of the design limits for the RV's and how competition aerobatics are flown.

    The +6 -3 limits are placard limits and the ultimate limits are +9 -4.5. No reason not to fly to +6 -3.

    Competition acro is like any other athletic activity. You build up tolerance through repetition of the building block figures. Focusing on precision you find that you do not have the mental attention units to be uncomfortable.

    If you fly one loop a month, its easy to find discomfort. If you fly +6 -3 three times a week like I do during the season, you don't even notice it.

    The original poster did not mention whether he currently owns an airplane. The first rule of aerobatic competition is bring an airplane. You can fly with a local aerobatic school and bring their airplane to find out whether you have the aptitude, desire, and budget for this sport. That is the easy way in. Some pilots find that a little taste is good enough. Some pilots find themselves selling all of their other toys and taking out a second mortgage to buy the highest performance ride that they can't afford. You don't know what is right for you until you show up at that first contest.

    Bringing an RV to a contest and flying Sportsman will not come close to approaching the G load limits of the airplane and will provide entry into the world of competition. If the original poster likes RV's, I encourage going forward. If the contest experience isn't what he expects, and RV is a great airplane for all of the other flying activities out there.

    As they say in the Nike ads - Justs Do It.

    Best of luck - See you at the box

    Wes
    N78PS

  4. #14
    RetroAcro's Avatar
    Join Date
    Jul 2011
    Location
    Cary, NC
    Posts
    105
    Quote Originally Posted by steveinindy View Post
    You get much beyond 5 or 6 g, especially if you're inverted and most people are going to find it downright unpleasant.
    Inverted? Most people find negative 3G unpleasant. But you're right, "much beyond 5 or 6 g" negative is downright unpleasant since in most cases you're now flying a broken airplane.

    Quote Originally Posted by steveinindy View Post
    My point about the RV series being unsuited was from the assumption that he had little background in aerobatics and was looking to go out and really tear it up. Even for 4.5 g, a marginal factor of safety of 25% would put the RV series at the lower end of the suitability spectrum and I wouldn't go beyond that level in an aircraft without a much higher design load tolerance.
    You seem very misguided about aerobatics and aerobatic airplanes. An RV is stressed according to the FAA's requirement for aerobatic aircraft...+6/-3G of operational load limit. This means the airplane is designed to be repeatedly subjected to this amount of stress without being detrimental to the airframe. These airplanes are required to have a 50% strength margin over +6/-3 built in, meaning they must sustain +9G before airframe deformaties occur. Not sure why you consider an RV to be any different from other aerobatic airplanes in this regard. You seem to be implying that only airplanes with greater than 6G of load limit are suitable. There are extremely few that fall into this category - basically the Unlimited monoplanes. This is to say that the many other aerobatic airplanes that have been flown for decades as trainers and as the first acro mount of many new aerobatic pilots are unsuitable. Nothing could be further from the truth. Your opinions come across as being uninformed by facts and experience, so when you say something like "I would recommend against the RV series" to the original poster who is seeking experience and advice, I feel the need to clarify these issues with you.


    Last edited by RetroAcro; 02-22-2012 at 10:13 PM.

  5. #15
    steveinindy's Avatar
    Join Date
    Jul 2011
    Location
    Indiana
    Posts
    1,449
    The +6 -3 limits are placard limits and the ultimate limits are +9 -4.5. No reason not to fly to +6 -3.
    I didn't think 6/-3 sounded correct since I'm used to (from a structural standpoint) hearing the ultimate load limit. That's where the confusion stemmed from.
    Unfortunately in science what you believe is irrelevant.

    "I'm an old-fashioned Southern Gentleman. Which means I can be a cast-iron son-of-a-***** when I want to be."- Robert A. Heinlein.



  6. #16
    BruceAir's Avatar
    Join Date
    Jul 2011
    Location
    Seattle, WA
    Posts
    26
    Dick Van Grunsven wrote about aerobatics in the RV series in "Approaching Aerobatics," a feature in the December 2000 issue of Sport Aerobatics, the magazine of the IAC. Those contemplating flying the RV series in competition and for recreational aerobatics should review that article.

  7. #17
    Has FULL spin testing been done on each RV aircraft type. Blown aerobatic maneuvers can result in all types of spins. Will the RVs go into flat spins easily, will they recover easily? Just something to consider.

  8. #18

    Join Date
    Oct 2011
    Location
    New Hampshire
    Posts
    985
    I will suggest two things. Dick Van G is very thorough. Someone else can check, but I would be very surprised if the RV aircraft have not been spin tested as thoroughly as normal category aircraft.

    Also, flat spins are over-hyped. The most common method to get into a spin in competition acro is to kick early for a hammer.... ask me how I know. The most important variables are CG and power. If you are within the aerobatic CG envelope and you pull the power to idle, the rest of the recovery is a non-event unless you were stupid enough to get into the situation below 1000' or you skip the training module on spin recovery altogether.

    The pilots that I see at IAC contests are most often flying RV-8's. Have not seen any of the side-by-side seating models. Those pilots look to be flying a forward CG's and I have not observed any issues with flying the figures.

    If anyone has hard data to contradict any of this info, please feel free to post.

    Best of luck,

    Wes
    N78PS

  9. #19
    Flyfalcons's Avatar
    Join Date
    Feb 2012
    Location
    Bonney Lake, WA
    Posts
    197
    Van's posted an excellent service bulletin on spins and even though it focuses on the changes made to the RV-7, it does show how much thought and effort they have put into their design. The last paragraph is especially important.

    http://vansaircraft.com/pdf/sb02-6-1.pdf
    Ryan Winslow
    EAA 525529
    Stinson 108-1 "Big Red", RV-7 under construction

  10. #20
    RetroAcro's Avatar
    Join Date
    Jul 2011
    Location
    Cary, NC
    Posts
    105
    Quote Originally Posted by Flyfalcons View Post
    Van's posted an excellent service bulletin on spins and even though it focuses on the changes made to the RV-7, it does show how much thought and effort they have put into their design. The last paragraph is especially important.

    http://vansaircraft.com/pdf/sb02-6-1.pdf
    Yes, good SB. Just wanted to note that Van's consideration of his design as "sport aerobatic" capable does not mean competition aerobatic flying would necessarily be outside the envelope of what is described here to be "sport aerobatics". Not all aerobatic airplanes are suitable for Unlimited aerobatics, which includes tailslides and outside snaps. RVs are generally only flown up to the Sportsman category, which consists of the basic figures many folks do when flying "sport aerobatics". The only difference between Sportsman competition and recreational sport acro is the standard of precision. Flying with precision does not require stressing the airplane more than doing lazy "flopping around" acro. Many folks have this misconception about contest flying.

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •