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JRB-4 and SNJ-5

Mon Mar 10, 2008 6:15 am

Good morning,

I am actually working on two restauration projects:

Beech JRB-4 and SNJ-5.

French administration give's me some headaches as they supsect a possible asbestos presence in those airplane (in fact they supsect asbestos presence in all airplanes!!!), and, in order to comply the actual regulation concerning asbestos, they asked me to remove it or to prove them there is none.

To my mind, I guess that asbestos might be present in brakes and may be in the cockpit heater system of JRB-4.
Parts Catalogue of the both airplanes doesn't tell so much about building materials.

I would be most grateful if somebody could help me with his personnal knowledge or indicate me an official documentation which could afford some light about this problem.

Thank you .

Best Regards.

ALU.

Mon Mar 10, 2008 7:00 am

Hello ALU,

There are three possible places for asbestos in the JRB-4. The brake pads like you mentioned, the exhaust heat shield and there might be asbestos wrapping around the outside of the 2 inch heater ducting.

The heat shield around the exhaust pipe is the most obvious one. This is only used if the aircraft has the original single exhaust pipe. If the Beech has been modified with 6 short exhaust stacks then the heat shield is no longer used.

The heat shield is a stainless steel wrapper covered with asbestos and it covers the exhaust pipe where it passes through the accesory section. It runs from the dishpan to the firewall.

Early Beech 18's also used aluminum flexible tubing from the heater valve to the front and rear cabin. This aluminum tubing was wrapped with asbestos tape to prevent heat loss. Once again this was only used on the original single exhaust stack system. If your Beech has been modified to have 6 short exhaust stacks on one engine then it will not have the heater valve and likely not have the old style asbestos covered 2 inch aluminum tubing.

I hope this helps. If you have any other questions about the Beech 18 or the JRB-4 please post here, e-mail me or PM.

Mon Mar 10, 2008 1:12 pm

The asbestos tape looks white or some off-white color. It should be around .060 thick. I have only seen it a few times and the best memory of it was some elect bundles were wrapped with it on the P-38. I have also seen it as a sandwich between layers of sheet. It has a cloth like texture IIRC.
Wouldn't it be better to keep it in place on an aircraft than remove it and subject it to be distributed to the environment?
Also don't tell them that Cad Plating is used on parts and hardware.
Rich

Sun Mar 16, 2008 5:11 pm

:D

Good Evening,

Thank you very much for your informations. I think it will be easy to remove asbestos from JRB-4.
It is not a personal choice to remove it, but I have to comply french regulations, which have been extended from house to cars and planes in order to prevent health problems.
I have to prove by now that I have removed all asbestos from the airplanes, or to prove there is none. I agree that there is quite no risk with an airplane containing asbestos!
Does someone could confirm me that SNJ-5 contains no asbestos?

Thank you for your help.

Best Reagrds.

ALU.

Sun Mar 16, 2008 5:56 pm

ALU wrote::D

Good Evening,

Thank you very much for your informations. I think it will be easy to remove asbestos from JRB-4.
It is not a personal choice to remove it, but I have to comply french regulations, which have been extended from house to cars and planes in order to prevent health problems.
I have to prove by now that I have removed all asbestos from the airplanes, or to prove there is none. I agree that there is quite no risk with an airplane containing asbestos!
Does someone could confirm me that SNJ-5 contains no asbestos?

Thank you for your help.

Best Reagrds.

ALU.

On the T-6 it might be on the stainless dishpan on the top where the tube which discharges the hot air from the heater mounted on the exhaust penetrates. At this point the alum tube which carries the hot air to the firewall connects. I have seen asbestos fabric mounted there as a seal from the tube to the S/S. There is also a possibility on the lower firewall there might be strips near MLG uplocks R & L. Also around engine mount attach lug holes.
Rich

Sun Mar 16, 2008 9:36 pm

I have also seen asbestos wrapping on very early cockpit heat tubes on the AT-6/SNJ series but they usually had a sleeve of insulation material called skyfelt (diamond stitch).

There was also an asbestos part in the gun port on the right wing. For lack of a better description it was shaped like a witches hat with the top snipped off. The snipped part was big enough for the diameter of the 30 cal ANM2 machine gun.

There is usually a band of asbestos around the opening for the cowl gun but these armament related items are quite rare in restorations let alone un restored aircraft as the gunnery gear was not used on all of the different models of the AT-6 and SNJ.

I thought of another spot on the Twin Beech that has asbestos. This one will be a lot harder to remove though. There is a gap seal around each engine mount lug as it comes through the firewall. It is a flat piece that has a metal flange holding it in place. This is an essential part of the firewall and helps to keep the fire from entering the nacelle. If you replace this please be sure to use an equivalent fire resistant material.

Mon Mar 17, 2008 8:36 am

Semi off topic, but asbestos is bad.

My father in law just passed away from mesothelioma, the cancer caused by asbestos. He was diagnosed in April of last year and passed away in November.

I know removal is a pain, but it could save a life.

Mon Mar 17, 2008 9:38 am

Clangjr,

I am sorry about your Father passing from Mesothelioma.

My concern for removing the asbestos on the firewall of the Twin Beech is not for the hassle of removing it but is for the danger if it is removed and not properly replaced.

If a fire develops in the engine accessory area it can spread into the nacelle through the openings normally closed by this asbestos material.

This material is critical to the integrity of the firewall and its simple removal could potentially cause a loss of life should a fire develop.

Once again I am sorry for your loss,

Taigh

Mon Mar 17, 2008 2:46 pm

Bonsoir monsieur "ALU", JRB-4 and SNJ-5 rebuilder,

Just wondering which projects you are working on. At Alencon, or ?

Merci beaucoup pour votre assistance.

Benno "T6" Goethals, Pays-Bas
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