Forum

Notifications
Clear all

This Forum is a place for Piper Comanche pilots to communicate and discuss technical issues

If you join or reset a password, please check your Spam Email box for emails from Admin at ComancheTechTalk.com

Please put your questions on the forum as well so everyone can read and respond. Someone else might be having similar questions.

All questions or topics on the Forums automatically get sent to the Tech team as well.

Do Tip Tanks need an STC?

1 Posts
1 Users
0 Reactions
573 Views
Admin
Joined: 5 years ago
Posts: 1162
Topic starter  

Do Tip Tanks need an STC?

Postby Nick Long » Fri Nov 18, 2011 12:30 pm

Hello everyone,

Do tip tanks need an STC? I have a PA30B I am parting out with wing tip tanks. The engineer who used to maintain the plane says they were an original Piper option so there is no STC.

In the aircraft paperwork, there are STCs and records for all sorts of things. But no mention of the tip tanks and no record of them being fitted after construction in 1966. There is mention of the fuel selection solenoids, though. So that all agrees.

I can't see a manufacturers name on the tanks themselves.

Is this correct; are they Piper originals?

Thanks

Nick

P1020846tip.jpg
Nick Long
 
Posts: 6
Joined: Tue Oct 11, 2011 6:39 pm

Re: Do Tip Tanks need an STC?

Postby N3322G » Fri Nov 18, 2011 2:33 pm

Nick,

Others will likely chime in - Tip Tanks were an option on my family's 1970 Twin Comanche PA39 but they didn't buy them at the time. My documentation shows them as a Brittain tank option.

In 1992 Mom bough the 15 gallon each Osborne tip tanks and had them installed. Yes, it took an STC. Osborne also holds the Shadin fuel computer STC to act as primary fuel flow gauge. http://www.jlosborne.com/preinstalled_tip_tank.htm

I don't know how it is handled from a parting out view.

Hope this helps a bit.

Pat

Patricia Jayne (Pat) Keefer ICS 08899
PA-39 #10 Texas

User avatar
N3322G
ICS member
ICS member
 
Posts: 1911
Joined: Thu May 08, 2008 1:58 pm
Location: Fort Worth, Texas area

Re: Do Tip Tanks need an STC?

Postby Kristin Winter » Sat Nov 19, 2011 4:10 pm

Piper often installed STC's at the factory as part of production. I believe that your tanks were installed by the factory as an STC'ed option, though a check of the Type Certificate Data Sheet might clarify. It is likely that anyone buying the tanks will need the STC to install them.

I happen to have a copy of the installation instructions. With all the parts and the installation instructions, a mechanic can make the installation. There is only the problem of the requirement in the U.S. that one have the permission of the STC holder. As it happens, I believe that law to be onconstitutional, but it hasn't been challenged yet.

Kristin
User avatar
Kristin Winter
ICS member
ICS member
 
Posts: 1299
Joined: Tue Aug 09, 2005 5:21 pm
Location: Northern California

Re: Do Tip Tanks need an STC?

Postby Zach Grant L1011jock » Sun Nov 20, 2011 4:27 pm

The tanks were sold by Piper as a Piper Kit, and as such were approved as manufacturer parts. If you install a Piper Kit, no STC is needed. If you install an aftermarket part, regardless whether it is the same, but didn't pass through the Piper hands to get approval, then you need an STC or field approval. Depending on the part number, you may or may not need the STC, HOWEVER, regardless of whether you are installing a Piper Kit, or an STC, it must be installed EXACTLY as certified, including all of the proper parts and part numbers. Where this gets tricky is if you are installing a Piper kit, but go to the STC holder for parts. If you do that, you need the STC...clear?
"Keep it above 5 feet and don't do nuthin dumb!"
User avatar
Zach Grant L1011jock
Technical Advisor
 
Posts: 1404
Joined: Mon Mar 22, 2004 4:35 pm
Location: Indianapolis KEYE

Re: Do Tip Tanks need an STC?

Postby Nick Long » Mon Nov 21, 2011 10:51 am

Pat, Kristin, Zach,

Many thanks for your replies.
Zach, would you expect "exactly as certified" to include using factory made up pipework and wiring rather than an engineer just connecting them up himself? As well as the tanks, I have the selector solenoid valves and the switches in the photo below; I'm assuming that makes a complete kit.

As an aside, I've got mixed feelings about the STC system. We don't have it over here in the UK, but if we did I might have been able to recoup some of my investment when I solved the braking problem on a certain British aircraft and got the mod approved.

Nick

P1020861tip.jpg
Nick Long
 
Posts: 6
Joined: Tue Oct 11, 2011 6:39 pm

Re: Do Tip Tanks need an STC?

Postby Zach Grant L1011jock » Mon Nov 21, 2011 12:15 pm

I would consider exactly to mean the piper parts with piper part numbers be installed as per the piper drawings. Once that happens, then any appropriately licenced person or facility can repair any part found faulty, or replace with a PMA part. Hope this helps. It is truly a two step process.

Zach

"Keep it above 5 feet and don't do nuthin dumb!"
User avatar
Zach Grant L1011jock
Technical Advisor
 
Posts: 1404
Joined: Mon Mar 22, 2004 4:35 pm
Location: Indianapolis KEYE

Re: Do Tip Tanks need an STC?

Postby Francois Marquis » Tue Nov 29, 2011 4:07 am

Hi all,

Sorry I am late into the conversation. This is my first post here, so maybe I can add my $0.02.

I am deeply invested into a rather complex import process into Canada of a 1968 B model PA-30 that sports the tip tanks. Going through the original weight and balance document I hit the original equipment and option list that was supplied by Piper. From that list, the TT-5 Brittain (now Osborne) tip tanks have STC SA727WE as the certification basis. Idem for the associated flight manual.

The same appears for the factory option turbochargers. It appears that the type certificate A1EA is not inclusive of the tip tanks nor the turbocharger options. As a secondary evidence, the TCDS (type certificate data sheet) found on the FAA website has no mention whatsoever of tip tanks, except for the type PA-40 which I believe is now part of history.

Therefore, any transfer of those would have to go through an STC installation process. I believe that Osborne can supply the documentation for a fee as they offered to me while I was researching for the documentation to support the above to Transport Canada.

Cheers
Francois Marquis
C-FTWK (as in twinkie :D )

Francois Marquis
 
Posts: 11
Joined: Mon Nov 07, 2011 5:02 am

Re: Do Tip Tanks need an STC?

Postby Zach Grant L1011jock » Tue Nov 29, 2011 5:03 am

Francois,
That may be true, but I can tell you that not one of the factory turbo aircraft came with any STC paperwork for either the turbos or the tip tanks. They were certified via STC, but they were supplied as Piper Kits, and as such, since Piper held a production certificate, they applied the Piper Kit associated with the option, and supplied the appropriate flight manual suppliment, and that was the extent of the paperwork. Many aircraft were field modified with these Piper Kits as well, which is what was entered on the 337 forms, not the STCs. The Piper flight manual reports were modified with additional suppliments, and that was all that was done. Another example of this was the deicing kits certified under STCs from Wiggins Aviation, but sold as Piper Kits/factory options. Confusing...yes, but using the information you provided above, all of these aircraft would be required to go back to the current STC holder and pay whatever fee for new STC and authorization paperwork, as well as remove the Piper flight manual supplements from the AFM, and insert the Rajay or Osbourne STC paperwork/flight manual suppliments, as well as file a new 337 listing the previous installation of said STC. Fortunately, this is not the case, and has been researched before, with the full blessing and documentation of both Piper and the FAA. If the STC was applied directly from Rajay, Brittain/Osbourne, and not supplied as a Piper Kit, then you are absolutely correct in the paperwork requirements.

Another little aside, the TCDS is not regulatory by the FAAs own order 86020.2A. It is a summary document with limited information that may be incomplete, and "it is neither a regulation, a maintenance requirements document, or a flight manual document...Any language on a TCDS, by itself, is not regulatory and is simply not enforceable" Just more confusion for the discussion!

-Zach

"Keep it above 5 feet and don't do nuthin dumb!"
User avatar
Zach Grant L1011jock
Technical Advisor
 
Posts: 1404
Joined: Mon Mar 22, 2004 4:35 pm
Location: Indianapolis KEYE

Re: Do Tip Tanks need an STC?

Postby Francois Marquis » Tue Nov 29, 2011 7:39 pm

I see your point Zach.

Not that I want to beat on this point of confusion any longer :shock: , but the same document have placeholders for ticking inclusion of the respective options into the AFM...

Whether this equates to other specific legal ramifications is beyond me... What the regulatory folks here wanted to know is whether "certification-wise" these were part of the plane or not and this showed it was not. What I read is that because that particular kit was factory install, it doesn't preclude it being re-installed on another aircraft under the very same STC it was originally certified unto.

An important aspect of such maneuver is the STC compliance by itself. My search for such demonstration pointed out to slight differences between the installation description in the original STC master drawing list and what was incorporated into the latest revision of Piper service manual, some 10 years later. I asked TC about who shall prevail and to them, the winner shall be the version at the date of installation prevailed. This may be questionable as what I have is the opinion of the fellow who will sign my aircraft... So that would need formal clarification/confirmation.

The differences I noted were being around fuel level indication logic and wire gauge from the Sol breaker. Non-negligeable aspects on a legal standpoint...

Cheers

Francois

Francois Marquis
 
Posts: 11
Joined: Mon Nov 07, 2011 5:02 am

Re: Do Tip Tanks need an STC?

Postby N3322G » Tue Nov 29, 2011 8:17 pm

Interesting discussion - thanks for sharing Zach and Francios
Pat

Patricia Jayne (Pat) Keefer ICS 08899
PA-39 #10 Texas

User avatar
N3322G
ICS member
ICS member
 
Posts: 1911
Joined: Thu May 08, 2008 1:58 pm
Location: Fort Worth, Texas area

Re: Do Tip Tanks need an STC?

Postby Mark in Perry » Thu Sep 27, 2012 3:27 am

hello all, hope this is not too far off topic, trying to verify tip tanks off a twin will work fine on a 250. any issues wrt wing attach or early vs late model lyear?
thanks for the help
Mark
Mark in Perry
ICS member
ICS member
 
Posts: 14
Joined: Sun Jan 03, 2010 6:44 am

   
Quote
Share: