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Spar mod one more time

Shortfinal

I'm New Here
Hello all
I am considering a RV3 built in 1984. It is being represented as being built w/ "double shear rear spar, a double spar bulkhead, a .32 ( do they mean .032") root rib and the straight carry-through". It has the conventional front fuel tank modified to 22 gallons along w/ a "fuel tank straddle mod".
So there are a lot of things going here. I was looking at VAN's Service Bulletin SB 96-3-1 dated 3/25/96 regarding the spar mod. I'm finding it strange that this airplane was built some 12 years before the mod came out but yet identifying a problem early on? The logs and paperwork are with the A/C and I may have missed something when I looked at them last week. Is there a way to visually verify these mods and that they were done properly? Done during the build or done later??
Lastly, without question I will get some professional eyeballs on the plane and it's documents before going much further, just trying to get my arms around the sequence of events, etc.
Thanks,
 
Good Luck with that;
When a builder goes off the reservation, it becomes more difficult to get help from 'The Tribe'.
These might be good and valid upgrades, made early in the RV-3 wing discovery process, by a proactive builder with talent.
VANs or an old hand in RV-3 construction and history would be where I would start. Eventually, if you buy this ship, you will have to take the time to become that authority.
There can't be too many of those for sale at any given time, so if it's the one I'm thinking it might be... I'd be right there too! Except I just finished my RV-8 !!
 
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Hi Gary

The Mods are well detailed on Randy L's site Link

IIRC the areas these looked at are:
  1. Beefing up rear spar attach - which is alluded to in your post
  2. Beef up rear spar in fuselage
  3. Reinforcing / doubling Root Rib - ditto (?)
  4. Reinforce Spar Web/Flange between Ribs
To be honest, the current Vans support I am not sure would be much help... largely post RV-3 era ;) The links from above give plans that someone can check against.
 
1982 Wing Mods

Hello Gary,
On the basis of multiple mishaps, the FAA issued a GENOT on March 16, 1981, which imposed a set of Operating Limitations on all RV-3 Aircraft.

In response, Van came out with an airframe modification, called Change Notice CN-1 in Feb 1982. The wing modifications that you describe were in all probability incorporated in response to this Change Notice.

As Andy Hill notes above, if you go to Randy's link and look under the "RV-3 Wing Spar Background" paragraph, you can download the original FAA GENOT and the Van's CN-1 instruction document, which includes copies of the four applicable drawings (CN-1-1 thru CN-1-4 of 2.18.82).

I assume that the airplane you are considering has the original main spar design. It is easy to tell by measuring the thickness of each of the multiple spar cap laminations. They will be 1/8" thick in wings built prior to the 1984 plans change to 3/16" thick laminations.

If the CN-1 modification was performed in accordance with the 1982 CN-1 document and drawings, the designation of the aircraft should have been changed from RV-3 to RV-3A.

After the 1984 plans changes, the next big wing event was the Feb 1997 Change Notice 2 modification called out for both 1/8" and 3/16" spars. This is also well described on Randy's site. It sounds like this major mod has not been performed on the airplane in question.

Regards, Hawkeye
 
Thanks to all who replied. What an interesting background on this subject. My questions have been well answered..
 
If this is the yellow -3 that's advertised here and elsewhere right now, there's wording in the ad to the effect that it was built to take a 200hp O-360. It also says it was built by "the Harmon guys" which may mean the people who did the engineering on the original Harmon Rocket... A currently well-proven design.

It would be worth talking to as many people as possible who were involved with the building of the aircraft to learn about the changes made at the time. They may have solved the strength issues using a different method, that may or may not have been equivalent. It might even be better.
 
Yes that's the one. The log book shows the initial engine as an IO360. It flew early on at the Sun-n-Fun races, there's an entry stating 225MPH. It was later changed to the current IO320. It's had few owners since and now needs some TLC.
From the comments here, I'm fairly certain it has the spar mods(at a minimum).

In addition to the TLC, I would like to end up w/ wing fuel and strangely, it has nav lights but no landing light - that would be a must have for me so maybe new wings which would make all this discussion sorta null.
 
Short, I researched this one as well and the mods, though not VANS method described in the CN, it may be just as good. I backed out after having no construction logs or documentation on flight tests after 320 installed. This is a good candidate for parts plane or rebuild project with updated wing. I think the R3 wing kit is 4k? Best of luck.
 
Thanks Ed
I would approach it as you've described - a project plane. In a perfect world new wings from VANs should "bolt right up".

But would they?
 
The RV 3 was produced long before Vans went to CAD/CAM production, and therefore the spars most likely will not simply bolt up to the existing fuse.

Best bet is to call Vans, I doubt if this is the first time the subject has come up.

Also, you could try calling Phlogiston and see if they have any ideas. They make the spars for Vans. http://www.phlogistonproducts.com/Services.html

If I were doing this job, I would seriously consider replacing the spar carrythrough setup in the fuse, yes a lot of work, but well worth it IMHO.

Good luck, keep us informed if you go ahead with this, and please show your work here for anybody who will follow in your footsteps.
 
If you were going to put a "B" (modern) wing on the airplane, you'd need a new center section and bulkhead - and Van's is set up to sell that as a kit if I recall correctly. It will be a bit of work - but certainly not impossible.
 
RV-3A Designation

I am considering the purchase of an RV-3, which has implemented Van's change notices CH-1 (aft spar & wing root rib mods) & CH-2 (main spar mods).

The unofficial RV-3 website includes links to Van's CN-1 & CN-2 change notices, as well as the early correspondence between Van and the FAA. This correspondence includes the original 3/24/81 GENOT (#8600-14, RWA 1/40 SVC B). This GENOT basically says that all RV-3 aircraft are prohibited from aerobatics, period. A follow-up GENOT was published 5/22/82 (#8600.25, RWA 2/100 SVC B), which supposedly outlines the procedure for lifting the aerobatic ban, for an individual airplane. Unfortunately, I cannot find a copy of this second GENOT (it does not appear in the GENOT list in faa.gov). I'm guessing that you must first implement CN-1 & CN-2, verify 6 G capability by flight testing, then apply to the FAA for a new airworthiness certificate, redesignating your RV-3 as an RV-3A.

Special Airworthiness Information Bulletin ACE-99-10 (Nov 24,1998) mentions the 2 GENOTS, but does not tell you how to get copies. This SAIB lists the Chicago Aircraft Certification Office as the FAA contact, but they are not answering their telephone (847-294-7358). Can anyone tell me how to get a copy of the second GENOT, or offer any more information on the subject?
 
Welcome to VAF!

Thomas, welcome to VAF.

Check with the good folks at Vans Aircraft, I suspect they will have the info you are looking for.
 
RV-3A Designation

I am considering the purchase of an RV-3, which has implemented Van's change notices CH-1 (aft spar & wing root rib mods) & CH-2 (main spar mods).

The unofficial RV-3 website includes links to Van's CN-1 & CN-2 change notices, as well as the early correspondence between Van and the FAA. This correspondence includes the original 3/24/81 GENOT (#8600-14, RWA 1/40 SVC B). This GENOT basically says that all RV-3 aircraft are prohibited from aerobatics, period. A follow-up GENOT was published 5/22/82 (#8600.25, RWA 2/100 SVC B), which supposedly outlines the procedure for lifting the aerobatic ban, for an individual airplane. Unfortunately, I cannot find a copy of this second GENOT (it does not appear in the GENOT list in faa.gov). I'm guessing that you must first implement CN-1 & CN-2, verify 6 G capability by flight testing, then apply to the FAA for a new airworthiness certificate, redesignating your RV-3 as an RV-3A.

Special Airworthiness Information Bulletin ACE-99-10 (Nov 24,1998) mentions the 2 GENOTS, but does not tell you how to get copies. This SAIB lists the Chicago Aircraft Certification Office as the FAA contact, but they are not answering their telephone (847-294-7358). Can anyone tell me how to get a copy of the second GENOT, or offer any more information on the subject?

The first line of the 1982 Van's CN-1 Notice states, "Purpose: To specify airframe alterations required on VAN'S AIRCRAFT RV-3 airplanes for re-designation to model RV-3A for the purpose of exempting them from limitations dictated by FAA GENOT RWA 1/40 SVC B, dated Mar. 24, 1981."

I could not find any references to the May 1982 GENOT that you refer to, but letters back and forth from the FAA Great Lakes Region to Van resulted in the recommendation of following procedure:
Perform CN-1, then apply for a new Airworthiness Certificate, incorporating the Operating Limitations listed by Van in the CN-1 document, plus any other local limits that may apply, and re-designate the aircraft as an RV-3A.

The CN-2 Notice in 1997 was more in the nature of a Service Bulletin, Mandatory For Aerobatic Flight, with no change in aircraft designation. I am not sure how the various local FAA offices now handle the CN-2 for an aircraft designated as an RV-3A, perhaps as a Major Modification, but there would probably be some new Phase 1 testing requirements. I am sure it would vary from region to region.

The prior or coincident completion of the CN-1 Change is a requirement of the CN-2 Change for Type I (1/8" lamination) spar wings. However, if an aircraft had incorporated the CN-1 airframe changes back in the old days, but the designation had never been changed to an RV-3A via a new Airworthiness Certificate, the original GENOT would still be limiting, and new Airworthiness/ Op Limits/ Phase I, II testing, and a change to RV-3A designation would now be required.
 
Thanks Robert

This is what I suspected. Do I apply for a new airworthiness certificate through the Chicago office or the one that covers my area, Western New York State?

Regards,
Pete Neal
Buffalo, NY
 
FSDO

This is what I suspected. Do I apply for a new airworthiness certificate through the Chicago office or the one that covers my area, Western New York State?

Regards,
Pete Neal
Buffalo, NY

Pete, I would check with some homebuilders in your area and see if a local FSDO has handled some or all of their recent certificate processes. (Hopefully someone on this list from the Buffalo area will chime in here).

From the map at http://www.faa.gov/about/office_org/field_offices/fsdo/index.cfm?state=NY
it looks like the Rochester office is the closest.

There are some variations in the process that relate to the date of issue of the current Airworthiness Certificate. Prior to the 90's, almost any major change to an EAB aircraft required a new Airworthiness Cert, but more recent dates will often allow a major change to be made, followed by a logbook entry and re-entry into an appropriate Phase I test program. That might be a moot point if the airplane you are considering never actually completed the re-designation process to RV-3A status.

I was disappointed a few years ago when I found that because my airplane's Airworthiness Cert was from the early 80's, I would have to start from scratch when replacing a C-90-8 with an O-200, but my local FSDO helped me to handle the whole re-certification process in a pretty painless manner.

Good luck on your efforts. It is rare to find a nice RV-3 or RV-3A for sale that has had the CN-2 spar mods performed.
 
Rochester FSDO to the Rescue

The logbook of the RV-3 that I'm buying has a signed entry by an A&I that CN-2 was performed. There is no entry concerning CN-1. The seller has made some visual checks for me, which confirm that key features of CN-1 are in place (e.g. rear spar attachment bolt is now in double shear). So it appears that CN-1 was included in the original build, but the builder's log was never passed on to subsequent buyers.

Earlier this week, I emailed the Rochester FSDO, describing my problem. The next day, I received a phone call from an FAA inspector, who told me that his boss had assigned him to help through the RV-3/3A redesignation process. He outlined the overall process and my options for documenting the details of the CN-1 mods. He then said that he would get back to me after he acquainted himself with CN-1 and its history. I'm impressed! Wouldn't it be great if all of our civil servants had that kind of attitude?
 
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