---------------------------------------------------------- RV-List Digest Archive --- Total Messages Posted Thu 03/24/11: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:25 AM - Re: RV6 fuel tank sealant (Ed Anderson) 2. 07:26 AM - Re: RV6 fuel tank sealant (RV6 Flyer) 3. 07:26 AM - Re: RV6 fuel tank sealant (RV6 Flyer) 4. 10:38 AM - Re: max gross weight test (thomas sargent) 5. 11:24 AM - Re: max gross weight test (Michael Kraus) 6. 11:51 AM - Re: max gross weight test (Charlie England) 7. 03:27 PM - Re: max gross weight test (Louis Willig) 8. 04:56 PM - Supercharged @ Sun-n-Fun (G3i Ignition) ________________________________ Message 1 _____________________________________ Time: 03:25:02 AM PST US From: "Ed Anderson" Subject: Re: RV-List: RV6 fuel tank sealant John, I have been flying with the sloshed tanks in an RV-6A since 1998 using both Mogas and 100LL with no problem (so far). My understanding is that if the tanks surfaces were properly prepared and the slosh properly apply there is no problem. However, with less "perfect" application, the slosh can and has broken away from the tank surfaces and blocked filters. This apparently can happen suddenly, although a number of folks have reported finding white flakes in their fuel filters before it got to that point. There used to be some folks who would take your tanks and clean out the slosh - but the cost was not cheap and I think they finally decided better in the long run just to build new tanks with proseal only. Ed Edward L. Anderson Anderson Electronic Enterprises LLC 305 Reefton Road Weddington, NC 28104 http://www.andersonee.com http://www.eicommander.com From: N81JG@aol.com Sent: Wednesday, March 23, 2011 11:53 PM Subject: RV-List: RV6 fuel tank sealant New subject--- Does anyone have experience with the sloshing agent used to seal the fuel tanks prior to about 1994? I have heard of the agent sloughing off and blocking fuel pickup. Is this a sudden occurrence without any warning? Should all the sloshed tanks be replaced with Prosealed tanks? This is not a problem with my RV7A, but the tanks in a friend's RV6A. John Greaves RV7A N781JG Redding, CA In a message dated 3/23/2011 2:44:43 P.M. Pacific Daylight Time, andrew.d.zachar@gmail.com writes: Flight Test Engineer. Worked in Kansas and North Carolina. But, I'm a young guy and don't have as much experience as a lot of guys who are probably reading this list, so full disclosure, most of my knowledge comes from various advisory circulars and flight test guides. Being a CFI has reinforced that I need to be conservative and being in Flight Test has reinforced that I need to seek other's experiences before embarking on stuff on my own. Modern flight test is a little like being a litigation attorney. We don't ever ask a question in the courtroom (fly a test) for which we don't already know the answer (have previous experience, data, or windtunnel predictions.) Surprises during any type of flight test are a bad, bad thing. I think with aft-CG testing of RVs, going slow is good advice, but I'm actually most interested in hearing the data from others' expansions. Did they expand slow or fast, what results did they see? Your shared experience is a good one to keep in mind. -az On Wed, Mar 23, 2011 at 2:09 PM, Louis Willig wrote: Andrew, this is an excellent post. Wish you gave us your "day job" description. It sounds interesting. I wasn't going to post on this question, since many members on this list have so much more experience than I have. However, as a 12 year RV-4 veteran, I just want to re-enforce your CG guidelines. Most of us quickly feel the effects of extra gross weight each time we take off after refueling, or take off or land with a passenger. What we don't "feel" as quickly or as often is the effects of pushing close to the CG limits. We are constantly making small adjustments in trim while always remaining within the envelope. It would be a shock to most of us if we made these adjustments to a plane that was loaded near the edge to start with. I had an "aft CG" experience many years ago with a passenger who weighed 240#. I don't know how he even fit in the back seat, but he did. And I didn't realize what I was doing ( yes, I was stupid). When landing, I failed to add extra speed, and the aircraft stalled sharply, dropped a wing, and raised my blood pressure. All this, in the blink of an eye, with no telltale to a novice like me. I was only 6 inches off the ground but you would have thought I was two feet high. No damage, but very embarrassing. This problem is probably more acute in the -4's and -8's. So we pay more attention to CG. Look, I am not experience or capable enough to advise anyone how to fly their RV. I just thought I would step in to say that an aft CG lightens the stick feel under some circumstances (when you are already slow and trimmed forward) and can help you learn the "Flying Farmer" routine very quickly. :-) Louis At 11:54 AM 3/23/2011, you wrote: I'm far from getting into phase 1 with my RV-7, but I have a little insight from my day job. We approach weight and CG changes with great care and in many small steps. Generally, someone like Van's will put weight and CG limits on the airplane because outside of those limits, some limit may be exceeded (this could be a handling requirement if it's a certified airplane, etc.). >From some guidance material, the effects of higher weights on the aircraft: =E8=8F=B1igher takeoff speed. =E7-=A2onger takeoff run. =E7=B4=90educed rate and angle of climb. =E7-=A2ower maximum altitude. =E7=99=BEhorter range (more weight lifted = more work done = more fuel required). =E7=B4=90educed cruising speed. =E7=B4=90educed maneuverability. =E8=8F=B1igher stalling speed. =E8=8F=B1igher landing speed. =E7-=A2onger landing roll. =E9=AB=ADxcessive weight on the nosewheel. The effects of adverse CG conditions can be: FWD CG causes problems in controlling and raising the nose AFT CG affects longitudinal stability, and can reduce the airplane=E7=97=B4 capability to recover from stalls and spins (decreased rudder and elevator moments due to shorter arm (distance) from CG to control surfaces). AFT CG also yields very light control forces. (This makes it easy for the pilot to inadvertently overstress the airplane.) FWD CG is also limited by elevator effectiveness at slow speeds. Anyway, the point is that by expanding the envelopes during testing, you can watch for these effects. If you do it slowly, you can watch for trends, instead of just going to the endpoint all in one go and getting yourself into a situation where something (like light longitudinal control forces) can get you into trouble if you aren't expecting it. Hope this helps. -az On Wed, Mar 23, 2011 at 10:16 AM, Ralph E. Capen <recapen@earthlink.net> wrote: <recapen@earthlink.net> I did mine in stages. It was pretty weird strapping in a bag of sand...... -----Original Message----- >From: thomas sargent <sarg314@gmail.com> >Sent: Mar 22, 2011 4:06 PM >To: rv-list <rv-list@matronics.com> >Subject: RV-List: max gross weight test > >I am just about done testing my 6A. I specified a max gross at 1720lbs and >will fly it at that weight in a couple days. (Empty weight was 1076.) I >know some planes have significantly higher max gross weights. So far in my >tests (all solo), weight doesn't seem to change behavior very much. > >Fully loaded the CG will be at 74.6" (in the 68.7 - 76.8 range), so it's >still more than 2" forward of the aft limit, although I haven't flown it >that far aft before. I think I've had it no further aft than about 72" or >72.5". > >Should I approach the max gross configuration in a few steps or is it >reasonable to just go for it in one flight? > >-- >Tom Sargent ======================= get="_blank">http://www.matronics.com/Navigator?RV-List ========== http://forums.matronics.com ========== le, List Admin. ="_blank">http://www.matronics.com/contribution ========== -- Andrew Zachar andrew.d.zachar@gmail.com ========== target="_blank">http://www.matronics.com/Navigator?RV-List ========== MS - k">http://forums.matronics.com ========== e - -Matt Dralle, List Admin. t="_blank">http://www.matronics.com/contribution ========== -- Andrew Zachar andrew.d.zachar@gmail.com ="http://www.matronics.com/Navigator?RV-List">http://www.matronics.com/ Navigator?RV-List s.matronics.com/">http://forums.matronics.com p://www.matronics.com/contribution">http://www.matronics.com/contribution ________________________________ Message 2 _____________________________________ Time: 07:26:58 AM PST US From: RV6 Flyer Subject: RE: RV-List: RV6 fuel tank sealant I followed the recommendations of Van's Aircraft that were in effect at the time of construction. I used the WHITE slosh painted over the Pro-Seal an d sloshed the rear baffle per the directions at the time. After 13.5 years of flying and 2=2C480 flying hours=2C there has been NO is sues. NONE has come off=2C flaked=2C or got into my gascolator. I know of one RV-4 that had a leak in the tank. A yellow slosh was added ov er the white slosh. The yellow slosh acted adversely on the white slosh an d crinkled everything up requiring that the tank be taken apart=2C cleaned =2C and resealed. The White Slosh is alcohol resistant and the Yellow Slosh is not. They are NOT compatible with each other. Gary A. Sobek "My Sanity" RV-6 N157GS O-320 Hartzell=2C 2=2C484+ Flying Hours So. CA=2C USA From: N81JG@aol.com Subject: RV-List: RV6 fuel tank sealant New subject--- Does anyone have experience with the sloshing agent used to seal the fuel tanks prior to about 1994? I have heard of the agent sloughing off and bloc king fuel pickup. Is this a sudden occurrence without any warning? Should all th e sloshed tanks be replaced with Prosealed tanks? This is not a problem with my RV7A=2C but the tanks in a friend's RV6A. John Greaves RV7A N781JG Redding=2C CA ________________________________ Message 3 _____________________________________ Time: 07:26:59 AM PST US From: RV6 Flyer Subject: RE: RV-List: RV6 fuel tank sealant I followed the recommendations of Van's Aircraft that were in effect at the time of construction. I used the WHITE slosh painted over the Pro-Seal an d sloshed the rear baffle per the directions at the time. After 13.5 years of flying and 2=2C480 flying hours=2C there has been NO is sues. NONE has come off=2C flaked=2C or got into my gascolator. I know of one RV-4 that had a leak in the tank. A yellow slosh was added ov er the white slosh. The yellow slosh acted adversely on the white slosh an d crinkled everything up requiring that the tank be taken apart=2C cleaned =2C and resealed. The White Slosh is alcohol resistant and the Yellow Slosh is not. They are NOT compatible with each other. Gary A. Sobek "My Sanity" RV-6 N157GS O-320 Hartzell=2C 2=2C484+ Flying Hours So. CA=2C USA From: N81JG@aol.com Subject: RV-List: RV6 fuel tank sealant New subject--- Does anyone have experience with the sloshing agent used to seal the fuel tanks prior to about 1994? I have heard of the agent sloughing off and bloc king fuel pickup. Is this a sudden occurrence without any warning? Should all th e sloshed tanks be replaced with Prosealed tanks? This is not a problem with my RV7A=2C but the tanks in a friend's RV6A. John Greaves RV7A N781JG Redding=2C CA ________________________________ Message 4 _____________________________________ Time: 10:38:11 AM PST US Subject: Re: RV-List: max gross weight test From: thomas sargent FWIW I did my first "heavy" flight today in the 6A. It was at about 1590 lbs (max gross set at 1720) with cg at ablut 73.9. Pitch was definitely light and it took a little longer to lift off, but it still seemed to climb pretty good - in the 1400 ft/min range on take off. That is with a fixed pitch cruise prop (Catto) and I didn't try to climb especially fast. I got up to 8000 and did some stalls and low speed turns. Nose is definitely light. It is definitely a little squirrellier at low speed. Seemed to want to drop the right wing when it stalled, but that was probably just me. They landed me (KRYN) with a quartering tail wind, which didn't help any. Definitely had to watch that pitch very carefully when flaring. Seemed to roll out for a loooong time too. Full gross wt. in my plane puts the cg at 74.8, still well forward of the limit and only 0.9 further aft than today's flight. I think I'll try that next time. -- Tom Sargent ________________________________ Message 5 _____________________________________ Time: 11:24:54 AM PST US Subject: Re: RV-List: max gross weight test From: Michael Kraus As your cg moves aft and you load increases, your pitch will become even mor e sensitive and you will notice increased sink rates. Carry in a bit more s peed on final and be ready on the rudder pedals. Ask any RV-4 pilot with >200 lbs behind the roll bar. Makes landing feel 'n ew' again :-) Sent from my iPhone On Mar 24, 2011, at 1:30 PM, thomas sargent wrote: > FWIW I did my first "heavy" flight today in the 6A. It was at about 1590 l bs (max gross set at 1720) with cg at ablut 73.9. Pitch was definitely ligh t and it took a little longer to lift off, but it still seemed to climb pret ty good - in the 1400 ft/min range on take off. That is with a fixed pitch c ruise prop (Catto) and I didn't try to climb especially fast. > > I got up to 8000 and did some stalls and low speed turns. Nose is definit ely light. It is definitely a little squirrellier at low speed. Seemed to w ant to drop the right wing when it stalled, but that was probably just me. > > They landed me (KRYN) with a quartering tail wind, which didn't help any. Definitely had to watch that pitch very carefully when flaring. Seemed to r oll out for a loooong time too. > > Full gross wt. in my plane puts the cg at 74.8, still well forward of the l imit and only 0.9 further aft than today's flight. I think I'll try that ne xt time. > > -- > Tom Sargent > > ========================== ========= ========================== ========= ========================== ========= ========================== ========= > ________________________________ Message 6 _____________________________________ Time: 11:51:27 AM PST US From: Charlie England Subject: Re: RV-List: max gross weight test On 3/24/2011 12:30 PM, thomas sargent wrote: > FWIW I did my first "heavy" flight today in the 6A. It was at about > 1590 lbs (max gross set at 1720) with cg at ablut 73.9. Pitch was > definitely light and it took a little longer to lift off, but it still > seemed to climb pretty good - in the 1400 ft/min range on take off. > That is with a fixed pitch cruise prop (Catto) and I didn't try to > climb especially fast. > > I got up to 8000 and did some stalls and low speed turns. Nose is > definitely light. It is definitely a little squirrellier at low > speed. Seemed to want to drop the right wing when it stalled, but > that was probably just me. > > They landed me (KRYN) with a quartering tail wind, which didn't help > any. Definitely had to watch that pitch very carefully when flaring. > Seemed to roll out for a loooong time too. > > Full gross wt. in my plane puts the cg at 74.8, still well forward of > the limit and only 0.9 further aft than today's flight. I think I'll > try that next time. > > -- > Tom Sargent Hi Tom, I'm a little uncomfortable with telling you this, because of of obvious 'apples/oranges' issues, but here goes. When I was doing transition training (from one taildragger to another), the guy doing the training suggested leaving the plane trimmed somewhat nose down when doing wheel landings. The logic for that a/c was that the pilot then doesn't need to force himself to *push* the stick when the mains touch; the nose down trim will do that with just a release of backpressure. Again, this is 'apples/oranges', but you might consider re-purposing that trick; it might buy you a little insurance against inadvertently pulling the nose up into a stall. If you've run out of trim, I might think carefully about re-weighing or re-calculating. Charlie ________________________________ Message 7 _____________________________________ Time: 03:27:35 PM PST US From: Louis Willig Subject: Re: RV-List: max gross weight test Charlie, I had several tailwheel instructors suggest trimming forward for wheel landings. But I was always afraid to wheel land ( the sight picture seemed strange). Many years later I tried their advice, and it worked. I also noticed that the "feel" of the aircraft when flaring and landing seems more honest and controlled. Many of the posts, so far, have shown consistent descriptions with what I felt when I flew overloaded and close to aft CG limits upon landing. I guess we all have tricks to make a nice landing. Mine is to keep the throttle a hair forward, and the nose trimmed forward of neutral when I wheel land and when I have my sweetheart aboard. This thread is what the RV-list is about. Thanks, guys. Louis >I'm a little uncomfortable with telling you this, because of of >obvious 'apples/oranges' issues, but here goes. > >When I was doing transition training (from one taildragger to >another), the guy doing the training suggested leaving the plane >trimmed somewhat nose down when doing wheel landings. The logic for >that a/c was that the pilot then doesn't need to force himself to >*push* the stick when the mains touch; the nose down trim will do >that with just a release of backpressure. > >Again, this is 'apples/oranges', but you might consider re-purposing >that trick; it might buy you a little insurance against >inadvertently pulling the nose up into a stall. If you've run out of >trim, I might think carefully about re-weighing or re-calculating. > >Charlie ________________________________ Message 8 _____________________________________ Time: 04:56:42 PM PST US Subject: RV-List: Supercharged @ Sun-n-Fun From: "G3i Ignition" Russ is flying his Supercharged 7 to Sun-n-Fun to show the blower set-up and I, Thomas, G3i guy, will be coming along also. We will be there talking performance mods, ignitions, and what-ever else we been up to on the go fast power stuff. Were leaving Wednesday morning and if we can skate into Lakeland before the air show @ 2:00 we will be on the field. If not, we will be hanging out at Cross City Airport (CTY) until we can get in. Find us on the field and ck it out, Russs cell, 970-215-3383, Thomass 303-906-6846 See ya there! (http://img827.imageshack.us/i/g3iignition01450x300.jpg/) -------- Thomas S. [url]www.G3ignition.com [/url][I]Follow G3i on Facebook. [/I] Read this topic online here: http://forums.matronics.com/viewtopic.php?p=334977#334977 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rv-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RV-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rv-list Browse Digests http://www.matronics.com/digest/rv-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.