Aft stub spar replacement beginning

[carusoam]

Note for @Hradec above…

-a-

[67 m20F chump]

Here is some pics of my wing.

[carusoam]

I fixed it!

All better now…

-a-

[67 m20F chump]

I was lucky.  I was able to find a wing that had been on a partedout plane.  My spar issue wasn’t close to being as bad as the one in this thread.  It wasn’t economic to do the work and I thought about parting it out and building a RV-8 many times.  In the end I always wanted a Mooney so I stuck it out.  
 

Even if you pay a reputable Mooney shop to do a prepurchase inspection things get missed.  

[Mkruger2021]

Wow, fantastic job...Congratulations....

[67 m20F chump]

7 hours ago, bluehighwayflyer said:

Well, it looks like you inherited bladders in the process, so at least there is a silver lining!  

Looking good!

Jim

I put them in with the wing.  I would rather take a beating than strip and seal Mooney tanks.  I don’t know what Al was thinking on this one.  

[47U]

2 hours ago, 67 m20F chump said:

I don’t know what Al was thinking on this one.  

I think that the wing tanks Al designed were removable from the wood wing (which was a work of art all by itself).

In all fairness, integral fuel tanks were the standard when Mooney adopted the all-metal wing and is still the standard today.  The fuel sealant the military used had a formulation change back in the mid ‘90s and became much more reliable.  I’m guessing that the experience level of the person stripping/sealing/resealing integral tanks is the major variable as to the longevity of the repair.   

Even so, if someone desires bladders, that’s their choice.  If you need more range, converting to bladders can get you the total fuel on board presumably quicker than the integral option.  Keep in mind however, wings with bladders installed should have a corrosion inspection at some interval, depending on your location and hangar status.

Until the Monroy STC is available again, I’d think Griggs would generate some sales by designing a hybrid system by adding their bladders to the wing bays adjacent to, and plumbed into, the integral fuel tanks.  If your sealant is in good shape, you can keep the factory design and gain additional fuel by installing bladders with only a partial weight penalty as opposed to going with a complete bladder installation.   

 As I soldier on with my 48 gallons total fuel onboard.

[Guest]

6 hours ago, 47U said:

I think that the wing tanks Al designed were removable from the wood wing (which was a work of art all by itself).

In all fairness, integral fuel tanks were the standard when Mooney adopted the all-metal wing and is still the standard today.  The fuel sealant the military used had a formulation change back in the mid ‘90s and became much more reliable.  I’m guessing that the experience level of the person stripping/sealing/resealing integral tanks is the major variable as to the longevity of the repair.   

Even so, if someone desires bladders, that’s their choice.  If you need more range, converting to bladders can get you the total fuel on board presumably quicker than the integral option.  Keep in mind however, wings with bladders installed should have a corrosion inspection at some interval, depending on your location and hangar status.

Until the Monroy STC is available again, I’d think Griggs would generate some sales by designing a hybrid system by adding their bladders to the wing bays adjacent to, and plumbed into, the integral fuel tanks.  If your sealant is in good shape, you can keep the factory design and gain additional fuel by installing bladders with only a partial weight penalty as opposed to going with a complete bladder installation.   

 As I soldier on with my 48 gallons total fuel onboard.

I’m not sure that wet wings were the standard at the time of the conversion to metal in the Mooney line up.  Beech use bladders, Piper Comanches use bladders, Boeing KC135 series use bladders, to name a few.  All of these pre date the Mooney wet wing.

Clarence

[Hradec]

On 3/22/2022 at 8:36 PM, hammdo said:

How's the progress?

-Don

Winter slowed me down. Too cold in the hangar. Aft stub spar completely  installed. Mow I have left upper soar cap corrosion. In process of removing tank sealant al spar cap. Hope to make big progress when wx gets better.

[hammdo]

@Hradec any closer?

-Don

[Igor_U]

On 3/27/2022 at 4:09 AM, M20Doc said:

 Boeing KC135 series use bladders, to name a few.  All of these pre date the Mooney wet wing.

Clarence

In the wing??

I think that would be correct to say KC135 has 16 bladders in the fuselage under the floor, but I believe Fuel tanks in wings are integral like 707, 727 etc... unless it's military thing as someone is always shooting at them.

Reason why Mooney tanks are (prematurely) leaking is for not using faiyng surface seal process during the building of the wing and only filet sealing after the wing (Ribs, spars and skins) are riveted. 

 

 

 

[amillet]

Igor, can you describe that process? Faying?

[Igor_U]

18 hours ago, amillet said:

Igor, can you describe that process? Faying?

Alan,

Fay surface seal is applied to the mating surfaces of the wing before the components are riveted. It is applied for corrosion protection (often on lower lobe of the fuselage), in wings, or with different sealant to the Fuel tank area.

Installer would apply it to the flanges of the ribs and mating surfaces of the skins (upper and lower) and spars. 

Let's say on the sketch below fuel tank is between Main spar, ribs 5 and 3 and FWD plate (fuel tank boundary) part 7.

All the upper mating surfaces are highlighted where would have applied Fuel Sealant and then riveted which would squeeze sealant out. Lower surface would be done the same way as well as spars. Mechanic then forms a filet seal with that squeeze out and adding additional sealant as needed. That's forms the seal between the mating parts (Faying surface seal) and Filet seal. This is how all "real" planes are done, big Boeings, BBD, Gulfstream and such. Not sure about KC135 being military tanker weigh/cost is not the factor.

Our Mooneys have only filet seal applied after wing was built. Having said that, years ago, on a Mooney List, someone mentioned Factory started doing it the right way, but I have no knowledge of it.

[Pinecone]

I wonder why and how they made the decision to do it the way they do?

And I wonder if there is not a product that could be applied to an assembled wing, after stripping, that would wick into the joint to provide a better seal?