Surprised annual discrepancy

Tom-D

Tom-D

Taxi to Parking
Joined
Feb 23, 2005
Messages
34,740
Display Name
Display name:
Tom-D
copied from the northwest flyers page

quote:
Not trying to scare anyone away from ownership, but this picture was just sent to me showing the main spar of my Grumman during annual:
end quote

picture below
 

Attachments

  • spar corrosion..jpg
    spar corrosion..jpg
    82.3 KB · Views: 576
Suffice to say I've got one at least as good now, but folks here will have to understand if I keep it to myself at least until the issue is resolved or out of my hangar...


Now on those Gumman spars, I've found using a 12ft 2x4 to shove a shop light down the spar from the wing tip allows for a good look at the inner surface of the sewer pipe.
 
Skylane81E said:
Suffice to say I've got one at least as good now, but folks here will have to understand if I keep it to myself at least until the issue is resolved or out of my hangar...


Now on those Gumman spars, I've found using a 12ft 2x4 to shove a shop light down the spar from the wing tip allows for a good look at the inner surface of the sewer pipe.
Click to expand...
I wish the Thread contained a better description of where the picture was taken.

AS I read the picture it seems to be corroded behind the sheet, and the products are pushing up on sheet we can see, thus the cracks and bulge.

I would hate to think we have a glue joint involved.
 
Rotor&Wing said:
Bet all those previous "cheap annuals" were worth what he paid.

That corrosion didn't happen overnight.
Click to expand...
...and should have been detected during the annual when a check of the spar through the inspection holes is required. There are also a number of anti-corrosion treatments in use in this area of the Grumman to prevent this from happening. This is a rather sad case of neglect.:(
 
Tom-D said:
I wish the Thread contained a better description of where the picture was taken.
Click to expand...
Folks familiar with Grummans will recognize the top of the spar, probably in the wing root area based on what I see.

AS I read the picture it seems to be corroded behind the sheet, and the products are pushing up on sheet we can see, thus the cracks and bulge.
Click to expand...
You're reading it wrong. The spar is just a hollow aluminum tube -- no "sheets" involved. This corrosion is on the top of the outside surface.

I would hate to think we have a glue joint involved.
Click to expand...
No, "we" don't. That appears to be on the top of the spar, which is relatively easily inspectable and part of the annual inspection. The only way this happened is if the plane went a very long time without proper inspection or care.

I know you have some personal issues with the way Grummans are constructed, but this is not an indication of any sort of generic problem, just a neglected airplane. I'm sure you'll find similar examples on the structures of neglected Cessnas, Beeches, Pipers, and even Fairchilds.
 
My Tiger gets a thorough look at the spars every year as per the checklist. This one must have sat outside for a long time without the proper inspections.

Which model Grumman is it Tom?
 
Anthony said:
My Tiger gets a thorough look at the spars every year as per the checklist. This one must have sat outside for a long time without the proper inspections.

Which model Grumman is it Tom?
Click to expand...

I have no idea, the aircraft as understand it is in Georgia at a major Grumman facility, getting it's annual.

this is a good example of why we should have type specific maintenance when you own some thing different.

Don't get me wrong, this was not an attack on Grumman, Corrosions is a problem shared by whole fleet of aluminum aircraft no matter how they are assembled.

read the thread here. http://www.pacificnorthwestflying.com/index.php?topic=8713.0
 
Last edited:
Costco has (or had) a "Whistler IC-3409PX" wireless inspection camera. My SO got me one for Christmas. It consists of a box about the size of a compact digital camera with a color LED screen attached.

The business end is a small color camera about the size of a butterbean that contains the camera itself plus a white LED that illuminates whatever the camera is looking at. This in turn is mounted on a 3 foot flexible cable (with another 3 foot extension if necessary). This cable connects to the camera box, which has its own internal rechargeable battery.

Two neat things ...

One, the color LED screen is detachable and you can have a hundred feet between the camera and the screen, wirelessly. The screen also has its own rechargeable battery.

Two, what you see on the screen is recordable on a small SD card that holds up to an hour of motion video OR you can take individual snapshot photos and record them. That way when the Feds come knocking at the door you can play the video back for any given annual and say, this is what it looked like when I inspected it on the date and time stamped on the video or the photo.

Makes that damfool Cessna 150 rudder AD a snap (so to speak).

$130.

Jim
 
weirdjim said:
Costco has (or had) a "Whistler IC-3409PX" wireless inspection camera. My SO got me one for Christmas. It consists of a box about the size of a compact digital camera with a color LED screen attached.

The business end is a small color camera about the size of a butterbean that contains the camera itself plus a white LED that illuminates whatever the camera is looking at. This in turn is mounted on a 3 foot flexible cable (with another 3 foot extension if necessary). This cable connects to the camera box, which has its own internal rechargeable battery.

Two neat things ...

One, the color LED screen is detachable and you can have a hundred feet between the camera and the screen, wirelessly. The screen also has its own rechargeable battery.

Two, what you see on the screen is recordable on a small SD card that holds up to an hour of motion video OR you can take individual snapshot photos and record them. That way when the Feds come knocking at the door you can play the video back for any given annual and say, this is what it looked like when I inspected it on the date and time stamped on the video or the photo.

Makes that damfool Cessna 150 rudder AD a snap (so to speak).

$130.

Jim
Click to expand...
Wow, that's great! Sporty's has the Aviation version of the same thing for $1310.99.

(just kidding!)
 
Tom-D said:
I have no idea, the aircraft as understand it is in Georgia at a major Grumman facility, getting it's annual.
Click to expand...
Sounds like TrueFlight in Valdosta. They have the type certificate and production equipment, and a lot of folks who know what they're doing.

this is a good example of why we should have type specific maintenance when you own some thing different.
Click to expand...
The Grumman AA-1/5 Maintenance Manuals cover this quite well for any A&P who can read and takes the time to do so. In fact, it's easier to check this area on a Grumman than most Pipers or Cessnas because of the simplicity of construction and ease of access to those area, especially with one of those video gizmos described above. The problem is IA's who either don't have the documentation for the work they do, or don't read it, or just don't do their jobs in a responsible manner. Annuals done in less than a day (unless there's a team of people involved) are a warning sign of such folks -- and that's on any plane in this class, not just a Grumman.
 
One of those gizmos is also highly useful for doing the horizontal stab spar attachment point inspection on the AA-5-series types described in the Maintenance Manual. Hard to see well with a mirror and a flashlight.
 
Ron Levy said:
One of those gizmos is also highly useful for doing the horizontal stab spar attachment point inspection on the AA-5-series types described in the Maintenance Manual. Hard to see well with a mirror and a flashlight.
Click to expand...


Good to know, our hangar queen tiger will be getting its first annual in a few years as soon as I clear the "flying" planes off my plate
 
Ron Levy said:
Sounds like TrueFlight in Valdosta. They have the type certificate and production equipment, and a lot of folks who know what they're doing.

The Grumman AA-1/5 Maintenance Manuals cover this quite well for any A&P who can read and takes the time to do so. In fact, it's easier to check this area on a Grumman than most Pipers or Cessnas because of the simplicity of construction and ease of access to those area, especially with one of those video gizmos described above. The problem is IA's who either don't have the documentation for the work they do, or don't read it, or just don't do their jobs in a responsible manner. Annuals done in less than a day (unless there's a team of people involved) are a warning sign of such folks -- and that's on any plane in this class, not just a Grumman.
Click to expand...
I can agree, it's quite straight forward and easy if (big if it seems) the work has been getting done. Otherwise easy tasks such as inspecting the nose gear can get time consuming (read expensive) in a hurry if it hasn't been done in several years.
 
Skylane81E said:
I can agree, it's quite straight forward and easy if (big if it seems) the work has been getting done. Otherwise easy tasks such as inspecting the nose gear can get time consuming (read expensive) in a hurry if it hasn't been done in several years.
Click to expand...
I know of quite a few cases where AA-5x's have been annualed by a Grumman-savvy mechanic, and found the nose strut clearly had not been pulled in decades, yet the annual was signed off year after year despite the clear and explicit requirement to do so in the annual checklist in the AA-5-series manual. See above about mechanics (including IA's) who cannot read.:no:
 
Ron Levy said:
...and should have been detected during the annual when a check of the spar through the inspection holes is required. There are also a number of anti-corrosion treatments in use in this area of the Grumman to prevent this from happening. This is a rather sad case of neglect.:(
Click to expand...

+1. :rolleyes:
 
Ron Levy said:
Sounds like TrueFlight in Valdosta. They have the type certificate and production equipment, and a lot of folks who know what they're doing.
Click to expand...
Ron,

How are they doing down there? I remember thinking their situation paralleled that of Commander the last 5 years or so...
 
Ron Levy said:
I know of quite a few cases where AA-5x's have been annualed by a Grumman-savvy mechanic, and found the nose strut clearly had not been pulled in decades, yet the annual was signed off year after year despite the clear and explicit requirement to do so in the annual checklist in the AA-5-series manual. See above about mechanics (including IA's) who cannot read.:no:
Click to expand...

where does it say the manufacturers inspection list or manuals must be used for an annual?

Good Idea.. Yes.
Mandatory ..No
 
Ron Levy said:
Annuals done in less than a day (unless there's a team of people involved) are a warning sign of such folks -- and that's on any plane in this class, not just a Grumman.
Click to expand...


There always seems to be mechanics out there that do this. Ive seen a lot of this type of activity (drive thru annuals) type operations and lots of owners flock to these types of operations because they are cheap.
 
Ron Levy said:
Sounds like TrueFlight in Valdosta. They have the type certificate and production equipment, and a lot of folks who know what they're doing.
Click to expand...
I'm sure they can do the annual quicker, and better than any A&P not totally familiar with the type.

Ron Levy said:
Grumman AA-1/5 Maintenance Manuals cover this quite well for any A&P who can read and takes the time to do so. In fact, it's easier to check this area on a Grumman than most Pipers or Cessnas because of the simplicity of construction and ease of access to those area, especially with one of those video gizmos described above. The problem is IA's who either don't have the documentation for the work they do, or don't read it, or just don't do their jobs in a responsible manner. Annuals done in less than a day (unless there's a team of people involved) are a warning sign of such folks -- and that's on any plane in this class, not just a Grumman.
Click to expand...

Any 100 series cessna, can be annulled in 1 day, and do it completely by Cessna 100 series service manual, you hit it hard for 8 hours and it will be complete.

Repairing discrepancies is a different matter.

Second question, The corrosion I'm seeing in the picture certainly looks like inter granular in the exfoliating stages. Apparently this is well known area to inspect, So, is this a chronic problem with the pipe grumman used as a spar?

Is this the reason there is a time life on the spar?
 
Last edited:
flyer said:
There always seems to be mechanics out there that do this. Ive seen a lot of this type of activity (drive thru annuals) type operations and lots of owners flock to these types of operations because they are cheap.
Click to expand...

Are you buying an annual inspection or a 13 month maintenance period?
 
Tom-D said:
Are you buying an annual inspection or a 13 month maintenance period?
Click to expand...


There are several shops around that ive seen do this and it makes it tough for us that are doing a true annual to make a living. Ive annual a few of those planes that has had "drive thru annuals" for many years and the owners are always unhappy at the number of discrepancies that I find due to neglect for many years.
 
Tom-D said:
where does it say the manufacturers inspection list or manuals must be used for an annual?

Good Idea.. Yes.
Mandatory ..No
Click to expand...


Never said that the other annuals were "illegal"


"ill-advised" is probably a better term
 
Tom-D said:
Any 100 series cessna, can be annulled in 1 day, and do it completely by Cessna 100 series service manual, you hit it hard for 8 hours and it will be complete.
Click to expand...
Right.:rolleyes:

Second question, The corrosion I'm seeing in the picture certainly looks like inter granular in the exfoliating stages. Apparently this is well known area to inspect, So, is this a chronic problem with the pipe grumman used as a spar?
Click to expand...
No, yes, and no.
Is this the reason there is a time life on the spar?
Click to expand...
No.
 
Tom-D said:
"Other manuals"

what's that?
Click to expand...

Annuals, meaning "scope and detail"

Leagal sure, but I've had a guy in here selling a Bo because his brother who owned it died as a result of one of those annuals on a Dakota. One nice thing about our repair station manual is that we MUST follow the manufacturers manual. When you've got that data to not use it...
 
Skylane81E said:
Annuals, meaning "scope and detail"

Leagal sure, but I've had a guy in here selling a Bo because his brother who owned it died as a result of one of those annuals on a Dakota. One nice thing about our repair station manual is that we MUST follow the manufacturers manual. When you've got that data to not use it...
Click to expand...

Did you actually read post 20?
 
Ron Levy said:
...and should have been detected during the annual when a check of the spar through the inspection holes is required. There are also a number of anti-corrosion treatments in use in this area of the Grumman to prevent this from happening. This is a rather sad case of neglect.:(
Click to expand...
Is it something that can be fixed at a cost less than a replacement aircraft?
 
Cap'n Jack said:
Is it something that can be fixed at a cost less than a replacement aircraft?
Click to expand...
Yes. Center spars are available (used from the usual Grumman sources, and I think True Flight can get you a new one), and it's maybe a couple of days work to pull the wings, pull the old one out, put another one in, and put the wings back on (try doing that on your Cessna or Piper). In fact, my "Tiger," which is really a Tigerized Cheetah, has the center spar from a Tiger that was damaged beyond repair. Just make sure it comes with proper time-in-service documentation if it's used, since it's a limited life component (12,000 hours, so don't worry about using it up in your lifetime), and without that documentation, it's junk.
 
Ron Levy said:
Yes. Center spars are available (used from the usual Grumman sources, and I think True Flight can get you a new one), and it's maybe a couple of days work to pull the wings, pull the old one out, put another one in, and put the wings back on (try doing that on your Cessna or Piper). In fact, my "Tiger," which is really a Tigerized Cheetah, has the center spar from a Tiger that was damaged beyond repair. Just make sure it comes with proper time-in-service documentation if it's used, since it's a limited life component (12,000 hours, so don't worry about using it up in your lifetime), and without that documentation, it's junk.
Click to expand...

I charge 4 man hours to replace a forward or rear spar carry thru on a 150-170-172-180-182, I can order the new skins and carry thru and they will be here in 5 days UPS Ground.
 
Ron Levy said:
Yes. Center spars are available (used from the usual Grumman sources, and I think True Flight can get you a new one), and it's maybe a couple of days work to pull the wings, pull the old one out, put another one in, and put the wings back on (try doing that on your Cessna or Piper). In fact, my "Tiger," which is really a Tigerized Cheetah, has the center spar from a Tiger that was damaged beyond repair. Just make sure it comes with proper time-in-service documentation if it's used, since it's a limited life component (12,000 hours, so don't worry about using it up in your lifetime), and without that documentation, it's junk.
Click to expand...

Is the picture a center spar? Isn't that the fuel tank?
 
Tom-D said:
Is the picture a center spar? Isn't that the fuel tank?
Click to expand...

The center spar is not a fuel tank on any of the Grummans. The wing spar is a fuel tank on the two-place Grummans but not the four-place Grummans.
 
Ron Levy said:
This I gotta see.
Click to expand...

It's relatively easy thing to do.. Support the wings in place pull the attach bolts, shave the heads of the rivets, pull the top cabin skin, and the carry thru comes with it.

I usually do it prior to painting and window replacement, when we are restoring the aircraft or repairing damage.

The first one I did it took me 4 days until I was shown not to pull the wings. requiring you to do all the cable stuff, or mess with the fuel system or the wires.

Corrosion is becoming a major problem in the aging aircraft fleet, And as I see Grumman is not exempt.
 
Last edited:
You must log in or register to reply here.
Back
Top