---------------------------------------------------------- Aerobatic-List Digest Archive --- Total Messages Posted Tue 08/03/04: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:52 AM - Re: RV aerobatic maneuver parameters (Matt Jurotich) 2. 06:24 AM - Re: Re: RV aerobatic maneuver parameters (Ken Balch) 3. 06:42 AM - Re: RV Acro (Scott Bilinski) 4. 08:08 AM - Re: Re: RV aerobatic maneuver parameters (Tedd McHenry) 5. 08:15 AM - Re: Re: RV aerobatic maneuver parameters (Tedd McHenry) 6. 08:20 AM - Re: RV Acro (Ron C) 7. 08:25 AM - Re: Re: RV aerobatic maneuver parameters Date: Mon, 2 Aug 2004 13:34:29 +0200 (\214rodkowoeuropejs... (Ron C) 8. 08:58 AM - RV Acro (Lee Taylor) 9. 09:36 AM - Re: RV Acro (Scott Bilinski) 10. 09:38 AM - Re: RV Acro (Tedd McHenry) 11. 10:55 AM - remove (Robert Miller) 12. 11:22 AM - Re: RV Acro (Rick Caldwell) 13. 11:37 AM - Re: RV Acro (Ken Balch) 14. 11:31 PM - Re: RV Acro (Tedi) ________________________________ Message 1 _____________________________________ Time: 05:52:18 AM PST US From: Matt Jurotich Subject: Aerobatic-List: Re: RV aerobatic maneuver parameters --> Aerobatic-List message posted by: Matt Jurotich From the RV web site The RVs have a design stress limit of +6 and -3Gs at aerobatic gross weights: 1375 lbs for the RV-4 and RV-6/6A, and 1600 lbs for the RV-7/7A, and RV-8/8A. This equates to an ultimate or failure limit of +9 and -4.5 Gs. Matthew M. Jurotich NASA/Goddard Space Flight Center Swales contractor to the JWST ISIM Systems Engineer m/c : 443 e-mail mail to: phone : 301-286-5919 fax : 301-286-7021 JWST URL: Subject: Re: Aerobatic-List: Re: RV aerobatic maneuver parameters --> Aerobatic-List message posted by: Ken Balch With respect to the RV-8, the aerobatic gross weight is 1550 for all wings built before Van's incorporated matched-hole construction into the -8's wing kit. RV-8s with wing kits manufactured since then (about three years ago), have an aerobatic gross weight of 1600. If you're not sure about an -8 you're considering purchasing, get the builder's serial number and check with Van's. The RV-8 does wonderful 'gentlemen's aerobatics', as Van's likes to put it. Rolling & looping figures are easy to do and spins are no problem at all. Remember that there are really two kinds of aerobatics: the kind that looks & feels good from the cockpit, performed only for the pilot's pleasure, and the kind that looks right to the judges and how it feels in the cockpit is irrelevant. The RV-8 excels at the former sort and, while it can be forced into performing the latter sort, it is a less than ideal platform for competition. The airplane is so clean and accelerates so fast that you'd need to pull more g to stay in the box than this plane should be subjected to. An RV-8 with a 200 hp c/s setup will easily fly along in the yellow arc at cruise (or aerobatic) power. There's almost 80 knots between Va & Vne, so it's very, very easy to over-g the airplane if you're trying to keep a competition routine in the box. With care & practice, it's certainly possible to do a sportsman sequence in the -8, but I wouldn't want to push it any harder than that. Regards, Ken Balch RV-8 N118KB Pitts Model 12 N612KB (under construction) Matt Jurotich wrote: >The RVs have a design stress limit of +6 and -3Gs at aerobatic gross >weights: 1375 lbs for the RV-4 and RV-6/6A, and 1600 lbs for the RV-7/7A, and RV-8/8A. This equates to an ultimate or failure limit of +9 and -4.5 Gs. > > ________________________________ Message 3 _____________________________________ Time: 06:42:34 AM PST US From: Scott Bilinski Subject: Re: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: Scott Bilinski There was a article in the RVator a while back and it discussed the preparation of an RV-4 for competition aerobatics. At 08:44 PM 8/2/2004 -0700, you wrote: >--> Aerobatic-List message posted by: Neil McLeod > >Yep, I've read that. I'd still like to hear the thoughts folks with >aerobatic experience both RV's and other types of aerobatic planes and any >comparisons they would like to make. I realize that the RV series is not >intended to be as aerobaticly capable as the One Design. > >Neil >----- Original Message ----- >From: "Scott Bilinski" >To: >Subject: RE: Aerobatic-List: RV Acro > > > > --> Aerobatic-List message posted by: Scott Bilinski > > > > > The best information I have seen is in the back of the builders manual. > > > > > > At 11:39 AM 8/2/2004 -0700, you wrote: > > >--> Aerobatic-List message posted by: "Neil McLeod" > > > > > > >I, for one, would like to hear about your experiences, I'm building a >RV-7 > > >with inverted systems. > > > > > >Neil McLeod > > > > > >-----Original Message----- > > >From: owner-aerobatic-list-server@matronics.com > > >[mailto:owner-aerobatic-list-server@matronics.com] On Behalf Of > > >CBRxxDRV@aol.com > > >To: aerobatic-list@matronics.com > > >Subject: Re: Aerobatic-List: RV Acro > > > > > >--> Aerobatic-List message posted by: CBRxxDRV@aol.com > > > > > >In a message dated 8/1/04 4:32:59 PM Eastern Daylight Time, > > >racaldwell@hotmail.com writes: > > > > > > > > > > I missed the question about RV aerobatics. I built & have a RV-6 and >also > > >a > > > > > > > > One Design and fly aerobatics in both. If someone wants some ideas of > > >these > > > > planes, let me know & I'll discuss my experiences. Or come to Central >Fl & > > > > > > > go flying with me. > > > > > > > > > >***Lurk mode off *** > > > > > >Central FL :) > > > > > > > > >Sal Capra > > >Lakeland, FL > > > My Home Page > > >http://hometown.aol.com/cbrxxdrv/index.html > > > > > > > > > > > > Scott Bilinski > > Eng dept 305 > > Phone (858) 657-2536 > > Pager (858) 502-5190 > > > > > > Scott Bilinski Eng dept 305 Phone (858) 657-2536 Pager (858) 502-5190 ________________________________ Message 4 _____________________________________ Time: 08:08:11 AM PST US From: Tedd McHenry Subject: Re: Aerobatic-List: Re: RV aerobatic maneuver parameters --> Aerobatic-List message posted by: Tedd McHenry On Tue, 3 Aug 2004, Matt Jurotich wrote: > From the RV web site > The RVs have a design stress limit of +6 and -3Gs at aerobatic gross > weights: 1375 lbs for the RV-4 and RV-6/6A, and 1600 lbs for the RV-7/7A, > and RV-8/8A. This equates to an ultimate or failure limit of +9 and -4.5 Gs. Matt's right. Does anybody know when this changed, and why? My RV-6 builder's manual definitely says plus AND minus 6 G, which I thought was "common knowledge" about RVs up until today. This is a very large and surprising change in the airplane's specifications. Tedd McHenry Surrey, BC, Canada ________________________________ Message 5 _____________________________________ Time: 08:15:06 AM PST US From: Tedd McHenry Subject: Re: Aerobatic-List: Re: RV aerobatic maneuver parameters --> Aerobatic-List message posted by: Tedd McHenry One aspect of RV aerobatics that might be of interest to some on the list: the RV handles a lot like a military training jet. One reason I picked an RV was that I was looking for something that had the feel and "fun coefficient" of the jets I instructed on in the Canadian air force. The first time I flew an RV I knew I had found it. The control feel is lighter, of course, and the speeds much less, but the feeling you get looping and rolling the plane, and the ease with which it performs those kinds of manoeuvres, are very jet-like. Tedd McHenry Surrey, BC, Canada ________________________________ Message 6 _____________________________________ Time: 08:20:33 AM PST US From: "Ron C" Subject: RE: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: "Ron C" Rick- Thanks for the post. I have a HR2 and am building a one design. I am very interested in your thoughts about the OD and its performance/flying qualities. A few questions: 1. What power plant/ prop combo do you have? 2. Who built your engine? 3. How did your overall weight come out? 4. How are stick forces and overall coordination of the Od versus your -6? Thanks. Ron Carter, Farmington, UT ---------------------------------------------------- This mailbox protected from junk email by MailFrontier Desktop from MailFrontier, Inc. http://info.mailfrontier.com -----Original Message----- From: owner-aerobatic-list-server@matronics.com [mailto:owner-aerobatic-list-server@matronics.com] On Behalf Of Rick Caldwell Subject: Re: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: "Rick Caldwell" --> I missed the question about RV aerobatics. I built & have a RV-6 and also a One Design and fly aerobatics in both. If someone wants some ideas of these planes, let me know & I'll discuss my experiences. Or come to Central Fl & go flying with me. Rick >From: N925WB1@aol.com >Reply-To: aerobatic-list@matronics.com >To: aerobatic-list@matronics.com >Subject: Re: Aerobatic-List: RV Acro >Date: Fri, 30 Jul 2004 22:31:13 EDT > >--> Aerobatic-List message posted by: N925WB1@aol.com > >About aerobatics on the RV... > >I don't have any personal experience in the type, but there was a fella >back >home (Warrenton, VA) who put an RV-4 through it's paces in the aerobatic >box >one afternoon. It wasn't his plane, and he's since passed away, so I >can't >really provide any more info. Point is, the RV's can do some manuevers. >I'm >sorry I can't give any more detail, but hopefully this will give you some >encouragement to find more information. > >-Wayne > > Dont just search. Find. Check out the new MSN Search! http://search.msn.click-url.com/go/onm00200636ave/direct/01/ == direct advertising on the Matronics Forums. == == == ________________________________ Message 7 _____________________________________ Time: 08:25:39 AM PST US From: "Ron C" Subject: RE: Aerobatic-List: Re: RV aerobatic maneuver parameters Date: Mon, 2 Aug 2004 13:34:29 +0200 (\214rodkowoeuropejs... --> Aerobatic-List message posted by: "Ron C" One of the best sources for detailed info on all aspects of the Vans series of A/C is the RV ator newsletter and the book 14 years of the rvator or what ever it is up to now a days. Back in the '80's Van wrote a lot more about his design philosophy and why he designed the 4 the way he did. The rvator has a lot of info about flying aerobatics in the 4 with detailed analysis of each maneuver and what to watch out for. Ron Carter, HR2 pilot/builder/owner. ---------------------------------------------------- This mailbox protected from junk email by MailFrontier Desktop from MailFrontier, Inc. http://info.mailfrontier.com -----Original Message----- From: owner-aerobatic-list-server@matronics.com [mailto:owner-aerobatic-list-server@matronics.com] On Behalf Of Tedi Subject: Re: Aerobatic-List: Re: RV aerobatic maneuver parameters Date: Mon, 2 Aug 2004 13:34:29 +0200 (\214rodkowoeuropejs... --> Aerobatic-List message posted by: "Tedi" -------Original Message------- From: aerobatic-list@matronics.com Subject: Aerobatic-List: Re: RV aerobatic maneuver parameters cut----------- thanks for exact instructions! That's really nice to hear that some of You are doing aerobatics and RV resists it well. Simply. I started looking for some quick build kit, easy to assemble, but giving ability for some aerobatic figures. I will ask again, what are +/- G param. of RV 4 and 6? Is this +6 / -3 ? What about inverted flight? Is this forbidden only due to engine? Van writes that RV is not 'aerobatic plane', but some basic figures are allowed. If inverted flight is allowed - superb, because man can do some advanced aerobatics (with low G). Tadeusz, PL == direct advertising on the Matronics Forums. == == == ________________________________ Message 8 _____________________________________ Time: 08:58:24 AM PST US From: "Lee Taylor" Subject: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: "Lee Taylor" GUYS: Those of you who have RV's, and want to do acro. From a long-time acro instructor. ALL of the RV's are designed with prop shaft extensions, and please be aware that this single factor is tremendously limiting in pulling any kind of "G" with these planes, or in doing any kind of high-angular-velocity changes. Remember that the prop is a tremendous gyroscope, and as such, when you introduce high angular rate changes, the forces on that gyroscope are tremendous, and when you add in the moment arm of that prop shaft extension, you are placing unrealistic loads on the crankshaft. If you continue with this action, the inevitable result will be, one day, that your prop instantaneously departs from the plane. There will be no warning, the crank will just break, and all that forward weight will be lost. Think about what that does to your CG, and then decide if you want to continue doing any kind of serious acro in your RV's. Van says that it is not an acro bird. He's right. It is a wonderful plane, but it isn't designed for this kind of flight. Lee Taylor ________________________________ Message 9 _____________________________________ Time: 09:36:30 AM PST US From: Scott Bilinski Subject: Re: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: Scott Bilinski > > ALL of the RV's are designed with prop shaft extensions, Are you sure? I dont have a prop spacer. Or are you talking fixed pitch only? I think they require a spacer. Scott Bilinski Eng dept 305 Phone (858) 657-2536 Pager (858) 502-5190 ________________________________ Message 10 ____________________________________ Time: 09:38:25 AM PST US From: Tedd McHenry Subject: Re: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: Tedd McHenry Lee: That's a good reminder about prop extensions, but I have to jump on something right away before it becomes a "meme." > Van says that it is not an acro bird. He's right. It is a wonderful plane, > but it isn't designed for this kind of flight. What Van says is, "By virtue of their wide speed range and relatively low wing loading, the RVs are quite good aerobatic aircraft." However, he also says, "Although RVs are capable aerobatic aircraft, we do not recommend them for serious competition aerobatics." He goes on to explain that the reason they don't recommend them for competition acro is that they pick up too much speed in descent which, when combined with their low 1-G stall speed (hence low manoeuvring speed), makes it tricky to keep them "in the box." Nothing to do with loads and stresses. There are many factors to consider regarding prop loads. First, prop gyro loads are torque, not bending, so they are not affected by the length of the prop extension. However, Gz does result in a bending moment at the crankshaft flange. The magnitude of this load depends, of course, on the weight of the prop, the G factor, and the length of the prop extension (if any). Since 1993, RVs have been available with the short cowl option, which allows the use of a 2.25" extension rather than a 4" extension. RVs can also use either FP wood props or CS metal props, which have very different weights. Doing "sport" aerobatics (which can easily be performed without exceeding 3 G in an RV) with a wood prop is not going to result in a crank fatigue problem, even if you have the 4" extension. There are plenty of RVs that have been flown this way for years, some for decades. Flying more aggressive manoeuvres with a CS prop would, of course, produce a much higher bending moment at the crank flange. I don't know whether or not it would be high enough to be of concern. RVs are, very definitely, designed for sport aerobatics. Tedd On Tue, 3 Aug 2004, Lee Taylor wrote: --- Tedd McHenry Surrey, BC, Canada DO NOT ARCHIVE On Tue, 3 Aug 2004, Lee Taylor wrote: > --> Aerobatic-List message posted by: "Lee Taylor" > > GUYS: Those of you who have RV's, and want to do acro. > From a long-time acro instructor. > > ALL of the RV's are designed with prop shaft extensions, and please be > aware that this single factor is tremendously limiting in pulling any kind > of "G" with these planes, or in doing any kind of high-angular-velocity > changes. > Remember that the prop is a tremendous gyroscope, and as such, when you > introduce high angular rate changes, the forces on that gyroscope are > tremendous, and when you add in the moment arm of that prop shaft extension, > you are placing unrealistic loads on the crankshaft. > If you continue with this action, the inevitable result will be, one > day, that your prop instantaneously departs from the plane. There will be > no warning, the crank will just break, and all that forward weight will be > lost. > Think about what that does to your CG, and then decide if you want to > continue doing any kind of serious acro in your RV's. > Van says that it is not an acro bird. He's right. It is a wonderful > plane, but it isn't designed for this kind of flight. > > Lee Taylor > > ________________________________ Message 11 ____________________________________ Time: 10:55:05 AM PST US From: Robert Miller Subject: Aerobatic-List: remove --> Aerobatic-List message posted by: Robert Miller Please remove my e-mail address from the aerobatic postings. Thanks bob ________________________________ Message 12 ____________________________________ Time: 11:22:22 AM PST US From: "Rick Caldwell" Subject: RE: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: "Rick Caldwell" Ron, My One Design has the 200 hp angle valve engine that was built up by Monty Barrett in Tulsa. I have a three blade wood Performance prop. The empty wt is 1,000#. The extra weight is from carbon/epoxy over the plywood wing. I didn't build this part and I would have used a lightwieght FG/epoxy layup. But still, the perfomance of the 1D is phenominal. I share a hangar with Steen Aerolab's yellow Skybolt with a Barrett six cyl engine & CS Hoffman and we climb about the same. The roll rate of the 1D makes the RV seem slow as Christnas. The control forces (I have spades) are very light and very little stick force change with Gz. The only bad manner the 1D has is that it requires airspeed to pull. I do not loop below 160 mph. The wing buffets if you pull too much going too slow. But then, it is a fast plane so it is easy to get speed. The RV-6 I have is a 160 hp/CS Hartzell (no prop extension). It is also fun to fly and about opposite to the 1D. Its wing just keeps holding on. I can pull up to loop from 120 kts. OK, it is not a round one but I can still keep the juice flowing thru the carb. The stick is heavier than the 1D and it does built up resistance with airspeed. The flying in the RV is more flowing and smooth compared to the competion aerobatics I practice in the 1D. The RV really does put a grin on your face as you fly thru Cuban 8's, cloverleafs, immelmans, barrelrolls, loops, reverse Cubans and then all the formation flying I do with other RVs. Not to mention it goes X-C just fine and comfortable. That can't be beat. I couldn't imagine spending a whole day in the 1D going straight & level. I would have to put pillows over the spar. Rick >From: "Ron C" >Reply-To: aerobatic-list@matronics.com >To: >Subject: RE: Aerobatic-List: RV Acro >Date: Tue, 3 Aug 2004 09:39:43 -0600 > >--> Aerobatic-List message posted by: "Ron C" > >Rick- > >Thanks for the post. > >I have a HR2 and am building a one design. I am very interested in your >thoughts about the OD and its performance/flying qualities. A few >questions: > >1. What power plant/ prop combo do you have? > >2. Who built your engine? > >3. How did your overall weight come out? > >4. How are stick forces and overall coordination of the Od versus your >-6? > > >Thanks. > Dont just search. Find. Check out the new MSN Search! http://search.msn.click-url.com/go/onm00200636ave/direct/01/ ________________________________ Message 13 ____________________________________ Time: 11:37:37 AM PST US From: Ken Balch Subject: Re: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: Ken Balch Lee Taylor wrote: >GUYS: Those of you who have RV's, and want to do acro. > From a long-time acro instructor. > > ALL of the RV's are designed with prop shaft extensions > Not true. While certainly the case with the earlier birds, the 'modern' RVs (the -7 & -8, anyway) do not require the prop extensions. My RV-8 (Lyc. IO-360-A1B6 & Hartzell c/s) doesn't have one. This was one of my deciding issues when I built the plane: I didn't want a bird with a prop extension. > Van says that it is not an acro bird. He's right. It is a wonderful plane, but it isn't designed for this kind of flight. > > True to a point. So long as one differentiates between 'sport aerobatics' & competition aerobatics, the RV can be safely flown throughout a wide range of maneuvers. Regards, Ken Balch RV-8 N118KB Pitts Model 12 N612KB (under construction) ________________________________ Message 14 ____________________________________ Time: 11:31:58 PM PST US From: "Tedi" Subject: Re: Aerobatic-List: RV Acro Date: Wed, 4 Aug 2004 08:31:31 +0200 (\214rodkowoeuropejs... --> Aerobatic-List message posted by: "Tedi" ho ho what a discussion I started ;)) so, simply, RV can do aerobatics, but shouldn't be used for teaching. I can be flown just for fun, not for judges. right? It was really interesting discussion about prop extension. I am newbe in RVs - please explain "One Design" - thanks Tadeusz Forgacz, PL info@bianco.pl -------Original Message------- From: aerobatic-list@matronics.com Subject: Re: Aerobatic-List: RV Acro --> Aerobatic-List message posted by: Ken Balch Lee Taylor wrote: >GUYS: Those of you who have RV's, and want to do acro. > From a long-time acro instructor. > > ALL of the RV's are designed with prop shaft extensions > Not true. While certainly the case with the earlier birds, the 'modern' RVs (the -7 & -8, anyway) do not require the prop extensions. My RV-8 (Lyc. IO-360-A1B6 & Hartzell c/s) doesn't have one. This was one of my deciding issues when I built the plane: I didn't want a bird with a prop extension. > Van says that it is not an acro bird. He's right. It is a wonderful plane, but it isn't designed for this kind of flight. > > True to a point. So long as one differentiates between 'sport aerobatics' & competition aerobatics, the RV can be safely flown throughout a wide range of maneuvers. Regards, Ken Balch RV-8 N118KB Pitts Model 12 N612KB (under construction)