Shoulder Harness Disconnects From Lap Belt Buckle

[Speed Merchant]

I have a 1984 Mooney 201. The shoulder harness frequently comes loose from the lap belt. I was told that I could replace the bolt and plastic spacer that connects the shoulder to the lap belt. I called Don Maxwell and talked to their parts person. She did not have bolts and spacers and suggested that I call Alpha Aviation. They also didn't have the parts. The person I spoke to at Alpha suggested heating up a plastic tube to get it to fit over the bolt. Has anyone actually done this? Has anyone replaced the stock belts with aftermarket belts? Any suggestions are appreciated.

Thanks!

[Pinecone]

If your belts are original, I suggest replacing them or at least rewebbing them.

There is an article in the April issue of Mooney Flyer about seat belts with links to a place that does rewebbing.  And they can replace hardware also.

I replaced my front one with inertial reels from Alpha Aviation.  If I did it again, I would probably put an inertial reel for the pilot and a normal harness for right seat.  The reel gets in the way when entering and egressing.

[Shadrach]

12 minutes ago, Pinecone said:

If your belts are original, I suggest replacing them or at least rewebbing them.

There is an article in the April issue of Mooney Flyer about seat belts with links to a place that does rewebbing.  And they can replace hardware also.

I replaced my front one with inertial reels from Alpha Aviation.  If I did it again, I would probably put an inertial reel for the pilot and a normal harness for right seat.  The reel gets in the way when entering and egressing.

Pilot inertia and manual for passenger was the standard forum recommendation when I did mine 10 years ago. Did you replace the stock belts because you disliked them or due to age?

[WilliamR]

@Speed Merchant not clear if you already have the plastic bushing or not. Likely not as that is usually the cause for the belt to come loose. The bushing is a Cessna part and can be purchased through Spruce. Once you get it, heat it in hot water and it will stretch over the post. I've also seen someone use a zip tire around the post. Looks trashy but works.

If the buckle is worn and comes off with the new spacer installed, you will need new hardware. Lots of places sell the hardware.

William

[Pinecone]

3 hours ago, Shadrach said:

Pilot inertia and manual for passenger was the standard forum recommendation when I did mine 10 years ago. Did you replace the stock belts because you disliked them or due to age?

Both.  Mainly age, but also was the start of changing from the 1986 mauve interior.

[201Mooniac]

I had mine rewebbed at the last annual and the company that did the rewebbing replaced the plastic rings and mine are nice and tight now.  If you are interested I can look up the company name that did the rewebbing, it wasn't Alpha.

[PeteMc]

As others have said, probably time for new belts if they are the originals.  

Issue with the the shoulder strap coming off is probably because the little nylon (maybe plastic) O-Ring that fits around the tab on the main buckle has broken off.  It can be replaced, but again, pending the age you may just want to have everything replaced. 

 

[Fly Boomer]

3 hours ago, 201Mooniac said:

If you are interested I can look up the company name that did the rewebbing, it wasn't Alpha.

Please do.  Eventually, we will all need it.

[201Mooniac]

15 hours ago, Fly Boomer said:

Please do.  Eventually, we will all need it.

I checked my logs and mine were rewebbed by Aviation Safety Products https://aircraftseatbelts.com/

[Speed Merchant]

On 4/10/2024 at 8:40 AM, Pinecone said:

If your belts are original, I suggest replacing them or at least rewebbing them.

There is an article in the April issue of Mooney Flyer about seat belts with links to a place that does rewebbing.  And they can replace hardware also.

I replaced my front one with inertial reels from Alpha Aviation.  If I did it again, I would probably put an inertial reel for the pilot and a normal harness for right seat.  The reel gets in the way when entering and egressing.

I am going to have seatbelt.com reweb and put new hardware on all my belts. Thank you for your post, I appreciate it.

[Speed Merchant]

On 4/10/2024 at 8:55 AM, Shadrach said:

Pilot inertia and manual for passenger was the standard forum recommendation when I did mine 10 years ago. Did you replace the stock belts because you disliked them or due to age?

My bird is 40 years old and it's time to have them  redone. The shoulder harness is driving me crazy because it comes loose frequently. It's a real safety concern. Thanks for your post.

[Speed Merchant]

On 4/10/2024 at 8:55 AM, Shadrach said:

Pilot inertia and manual for passenger was the standard forum recommendation when I did mine 10 years ago. Did you replace the stock belts because you disliked them or due to age?

They are 40 years old and it's time for them to be renewed it's a real safety concern. Thanks for your post.

[Speed Merchant]

On 4/10/2024 at 8:40 AM, Pinecone said:

If your belts are original, I suggest replacing them or at least rewebbing them.

There is an article in the April issue of Mooney Flyer about seat belts with links to a place that does rewebbing.  And they can replace hardware also.

I replaced my front one with inertial reels from Alpha Aviation.  If I did it again, I would probably put an inertial reel for the pilot and a normal harness for right seat.  The reel gets in the way when entering and egressing.

Yep they are 40 years old they need to be replaced it's a real safety concern. Thank you for your post.

[Speed Merchant]

On 4/10/2024 at 11:31 AM, WilliamR said:

@Speed Merchant not clear if you already have the plastic bushing or not. Likely not as that is usually the cause for the belt to come loose. The bushing is a Cessna part and can be purchased through Spruce. Once you get it, heat it in hot water and it will stretch over the post. I've also seen someone use a zip tire around the post. Looks trashy but works.

If the buckle is worn and comes off with the new spacer installed, you will need new hardware. Lots of places sell the hardware.

William

There was no plastic part on the lap belt to keep the shoulder seat attached. I am sending them in to be renewed. Thanks for your post.

[Shadrach]

21 minutes ago, Speed Merchant said:

They are 40 years old and it's time for them to be renewed it's a real safety concern. Thanks for your post.

I’m not saying that it’s not a real safety concern. I will say that seatbelt health can be determined visually. UV damage presents as cupping or warping in the webbing. Tearing, fraying or “pilling” on the webbing surface is also a concern. 

Any belts manifesting the above conditions should be replaced or re-webbed. 

I still have the belts that I removed from my aircraft in 2010. They are still in fine shape at 57 years old having been in a hangared Aircraft all their lives.

[Pinecone]

On 4/11/2024 at 9:21 AM, 201Mooniac said:

I checked my logs and mine were rewebbed by Aviation Safety Products https://aircraftseatbelts.com/

Great people.

I had them do rewebbing for both my planes.

[Pinecone]

23 hours ago, Shadrach said:

I’m not saying that it’s not a real safety concern. I will say that seatbelt health can be determined visually. UV damage presents as cupping or warping in the webbing. Tearing, fraying or “pilling” on the webbing surface is also a concern. 

Any belts manifesting the above conditions should be replaced or re-webbed. 

I still have the belts that I removed from my aircraft in 2010. They are still in fine shape at 57 years old having been in a hangared Aircraft all their lives.

No, damage cannot always be seen.  

I learned this in shopping and dealing with parachutes.  They do pull testing on the canopy material and found issues, and that is always inside the container.

Up to you, but I would not continue to fly with 57 year old belts.

[Shadrach]

45 minutes ago, Pinecone said:

No, damage cannot always be seen.  

I learned this in shopping and dealing with parachutes.  They do pull testing on the canopy material and found issues, and that is always inside the container.

Up to you, but I would not continue to fly with 57 year old belts.

I’m flying with 12 year old belts. My 57 year old belts are in a drawer. I am grateful they are not made from parachute canopy material! 
 

do you know of any NTSB reports that include seatbelt failure as a contributing factor to injury or death?  I’ve done a cursory search and have found none.
 

 

[EricJ]

44 minutes ago, Shadrach said:

I’m flying with 12 year old belts. My 57 year old belts are in a drawer. I am grateful they are not made from parachute canopy material! 
 

do you know of any NTSB reports that include seatbelt failure as a contributing factor to injury or death?  I’ve done a cursory search and have found none.

We had a race safety seminar years ago where one of the reputable manufacturers went through the history of belt/harness safety development, and much of the driving research on material was Army aviation and other military aviation research into harness aging.   The Army had particular issues since the main aging mechanism turned out to be UV, and their helicopters spent much of their life on the ramp parked in the sun.   They had apparently had some failures, too, but I don't have anything to cite on that.

There have been failures in racing, with Dale Earnhardt being a notable case, which was aggravated by an installation issue.   FWIW, in racing harnesses age out fairly quickly and are considered one-time use.   The track safety guys typically chop up a harness after a crash so it can't be used again.   I got a nearly new harness handed back to me in pieces once after a crash.

Since airplanes tend to get used for a long time, it can definitely be an issue if the belts aren't refreshed once in a while. 

Edit: Just to be a little more complete, a harness is designed to stretch/yield a certain amount in a crash as part of the energy absorption characteristic to let you decelerate at a more survivable rate.    Over time both use and age affect the stretch characteristics of the material so that it can no longer be expected to perform as intended.   Re-webbing with new material or replacement of the harness restores the intended elasticity/plasticity of the harness.

 

[Brent]

On 4/10/2024 at 8:31 AM, WilliamR said:

@Speed Merchant not clear if you already have the plastic bushing or not. Likely not as that is usually the cause for the belt to come loose. The bushing is a Cessna part and can be purchased through Spruce. Once you get it, heat it in hot water and it will stretch over the post. I've also seen someone use a zip tire around the post. Looks trashy but works.

If the buckle is worn and comes off with the new spacer installed, you will need new hardware. Lots of places sell the hardware.

William

I bought the nylon spacers from Aircraft Spruce and heated them up as WilliamR suggested. It took my wife lending a hand and a couple cuss words, but we were able to get the spacers over the head on the buckle. All good now.