Looking for correct drawings for AWB 2500 Skis

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mdpesky
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Looking for correct drawings for AWB 2500 Skis

Post by mdpesky »

Hello Everyone

I am wanting to install a set of Federal AWB 2500 Wheel Ski's to my 1954 170B and am in "desperate need" for the correct drawings for same. According to the type certificate I need the following:

Hydraulic System Drawing Federal 11R1153.

I already have the Federal Rigging Drawing 11D1077,

Any advise on setting up the ski's and hydraulics would be greatly appreciated.

Also, does anyone know the technical difference between Federal AWB 2500 and AWB 2500A skis?

Mark
MDPesky:1954 C-170B/C145/Horton Stol, 1960 C-182C/520ci/Sportsman/Vortex/Wing-X/Alaskan Bush Wheel/Atlee Dodge/Ext-bag/Belly-Pod, 2013 Zenair CH750/912iS, 1999 Europa Tri-Gear/914 Turbo
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n2582d
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Re: Looking for correct drawings for AWB 2500 Skis

Post by n2582d »

Mark,
You might try Wipaire, the current owner of the Federal Ski type certificate. Skiplane.org might be another place to ask as would Dr. Jill Oakes in Winnipeg.
Gary
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mdpesky
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Re: Looking for correct drawings for AWB 2500 Skis

Post by mdpesky »

Hi Gary

Thanks for the response, we did get the rigging drawing from Wipaire but no Hydraulic drawings. I will try the other two you suggest, hopefully someone will have that elusive hydraulic System drawing 11R1153???

Mark
MDPesky:1954 C-170B/C145/Horton Stol, 1960 C-182C/520ci/Sportsman/Vortex/Wing-X/Alaskan Bush Wheel/Atlee Dodge/Ext-bag/Belly-Pod, 2013 Zenair CH750/912iS, 1999 Europa Tri-Gear/914 Turbo
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n2582d
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Re: Looking for correct drawings for AWB 2500 Skis

Post by n2582d »

Mark,
I'm curious where you found those document numbers. When searching for the Transport Canada C-170B type certificate T.C. says they have "accepted the foreign certificate without issuing its own certificate" and provide a link to the FAA's website.

The FAA's type certificate for the C-170B lists Federal AWB 2500 wheel-skis in item 208(g). There it refers to Federal installation drawing 11R549. Because these skis are listed in the TCDS no STC is required (in the U.S. at least). Looks like "Green Bean" may be able to help with drawing 11R549. See here.
Gary
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mdpesky
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Re: Looking for correct drawings for AWB 2500 Skis

Post by mdpesky »

Hi Gary

The copy of the type certificate I have was revised Nov. 5, 2004, and shows as you indicate under 208 "G" rigging drawing 11R549 for the AWB 2500 ski's. This drawing shows the cables attaching to the upper gear leg. This installation/drawing has an AD against it 54-02-02 which shows you must instead comply with Federal Rigging Drawing 11D1077 which attaches the front cables to the bottom engine mount and rear cables to the fuselage. I've heard that the original rigging to the gear leg was flawed leading to a potential ski flip and know of one case in the early eighties of a C170 rigged this way that ultimately failed and wrecked the aircraft. Why an aircraft was rigged in the eighties to a drawing with an AD against it is published much earlier is beyond me, but it was.

This brings me to a slight paranoia to make sure I have the absolute latest info resulting in the proper installation, confusing at best to confirm sometimes.

Even though it was only a week ago, I can't find my original reference sighting also that I need Federal Hydraulic Rigging Drawing 11R1153 to complete the hand pump, oil tank and hydraulic lines installation? If anyone has that a copy would be greatly appreciated!

Lastly, if anyone has more up to date info, or sees that I'm heading down the wrong path, I'd really appreciate them letting me know.

Mark
MDPesky:1954 C-170B/C145/Horton Stol, 1960 C-182C/520ci/Sportsman/Vortex/Wing-X/Alaskan Bush Wheel/Atlee Dodge/Ext-bag/Belly-Pod, 2013 Zenair CH750/912iS, 1999 Europa Tri-Gear/914 Turbo
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mdpesky
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Re: Looking for correct drawings for AWB 2500 Skis

Post by mdpesky »

Ok, reviewing my information I see the AWB-2500A Rigging Drawing sights the correct Hydraulic System Installation Drawing is #11R1153 for setting up the Hydraulic system. Rigging drawing 11D1077 which appears to be the later version sighted in the AD and which covers both the AWD-2500 and AWD-2500A skis makes no mention of the correct Hydraulic rigging drawing?

Confused yet, I am??

Also, some of the drawings, like 11R1061 show the use of front cable bungies, drawing 11D1077 shows straight cables with no bungies, how does that work?

If anyone has a correct AWB-2500 ski installation on a Cessna 170B, I'd really appreciate photos and any other information you can provide.

Mark
MDPesky:1954 C-170B/C145/Horton Stol, 1960 C-182C/520ci/Sportsman/Vortex/Wing-X/Alaskan Bush Wheel/Atlee Dodge/Ext-bag/Belly-Pod, 2013 Zenair CH750/912iS, 1999 Europa Tri-Gear/914 Turbo
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ddr36d
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Re: Looking for correct drawings for AWB 2500 Skis

Post by ddr36d »

Mark,
I had the AWB2500A skid on my '57 180 & have the drawings for that installation. I think they also cover the 170B.

I'm travelling home from Utah & should be there by the weekend. I'll check the drawing #''s.
Don
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mdpesky
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Re: Looking for correct drawings for AWB 2500 Skis

Post by mdpesky »

That would be great Don, really appreciate that!

Let me know......Mark
MDPesky:1954 C-170B/C145/Horton Stol, 1960 C-182C/520ci/Sportsman/Vortex/Wing-X/Alaskan Bush Wheel/Atlee Dodge/Ext-bag/Belly-Pod, 2013 Zenair CH750/912iS, 1999 Europa Tri-Gear/914 Turbo
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ddr36d
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Re: Looking for correct drawings for AWB 2500 Skis

Post by ddr36d »

Mark,
I have Drawing # 11R1153 for the hydraulic system installation with the reservoir and pump together. I also have Drawing # 11G1468 which is for a remote firewall mounted reservoir. This drawing is for the C3000 skis on C170 series and C180 thru C180F. This is the one I used for the installation I did on the 180.

I also have Drawing # 11R889 for the rigging installation. This one has a bungee in the front cable to lower engine mount for the 180 but just a cable for the 170.

I have Drawing # 10B2021 for weight and balance data and # 11R1002 for the AWT tail ski installation.

My drawing # 11R1153 is a little difficult to read. I think the best thing to do would be to mail it to you to use and then send it back. You probably could get a copy made.

My phone # 231-499-3974

Don
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JohnNielsen
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Re: Looking for correct drawings for AWB 2500 Skis

Post by JohnNielsen »

I am installing the same AWB2500 skis to my '55 170B. The axles and control arm remains in place with wheels and skis. When we had the floor out, we installed new 1/4" lines, tees and bulkhead fittings. The pump is mounted just between the front seats and touches the front edge of the rear seat. It restricts full aft movement of the eats by about 2". The tank is mounted to the pump/valve assy. It took a lot of custom design and fabrication to get all the parts to fit tightly together and not require removal of the rear seat or more than 2" of reduced aft travel of the front seats. I can take some pics and post here. I love the simplicity and common sense of the old school of drawings and instructions of CAR 3 and 1955 where it says "mount the pump and tank in a convenient location that will not obstruct or interfere with the use or access to other controls of the aircraft." My cables are the bungee style and mount to tangs on the lower engine mount and the float fittings on the rear. Going to try to get them all mounted and tested this week.
John
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mdpesky
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Re: Looking for correct drawings for AWB 2500 Skis

Post by mdpesky »

I have now received the appropriate drawings in the mail from Don and its really helped to sort this out. In return I shall make copies and on Don's behalf a set will be sent to the 170 association for others future reference. Thanks for that Don, its really appreciated! Not many people would send some stranger all his original drawings to help a guy out, WOW, the world still has nice people!!!

As mentioned by John Nielsen the hydraulic drawings leave you lots of flexibility which is a good thing. Unlike John we have decided to mount the pump on top of the tunnel between the trim wheel and the control stick, placing the bulk of it actually under the dash. This set up is the least intrusive to the pilot and passenger and should be a comfortable position for reaching the lever for pumping. That said the pump lever will end up rather short, maybe 11" to 12" to clear under the bottom of the panel.

This brings up the question, does anyone have any experience on how hard it is to pump the handle with a 1500psi rated pump on AWB 2500 Skis?

I ask because I will end up with a rather short leverage advantage with the pump mounted as I propose, I'm hoping I have enough leverage, can anyone tell me just how much force it takes?

Mark
MDPesky:1954 C-170B/C145/Horton Stol, 1960 C-182C/520ci/Sportsman/Vortex/Wing-X/Alaskan Bush Wheel/Atlee Dodge/Ext-bag/Belly-Pod, 2013 Zenair CH750/912iS, 1999 Europa Tri-Gear/914 Turbo
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Roesbery
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Re: Looking for correct drawings for AWB 2500 Skis

Post by Roesbery »

If you mount the pump directly to the tunnel, you will get quite a bit of flexing of the tunnel. And yes it can take some muscle power sometimes. Mine is mounted to a plate attached to the floor and left side of the tunnel so that the pump is just above the tunnel and left of the flap handle between the seats. The pump handle is along the top of the tunnel to the left of the trim. Takes a lot of the stress off the tunnel. The valve is mounted just behind the fuel selector with a # 6 (3/8) pipe to the reservoir mounted on the engine side of the firewall. # 4 lines go under the floor to the outside skin near the brake lines. It is pretty much out of the way and is left in place. Makes installing and removing the skis quick. Been working good for many years
howitzer_flyer14
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Re: Looking for correct drawings for AWB 2500 Skis

Post by howitzer_flyer14 »

Hey guys,

I'm a new member to the forum! This is my first post. I've been trying to hunt down ski axles and the drawings for AWB 2500 hydraulic wheel skis. I have the Venturi still so a top cowling mount for the bungees may not work. I'd be interested in seeing some pictures of other folk's mounting systems and how they mounting the hydraulic pumps inside.

Cheers,

Howard

1956 170B
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JohnNielsen
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Re: Looking for correct drawings for AWB 2500 Skis

Post by JohnNielsen »

Here are some pics of my AWB pump and ski installation. I quick fit the right side ski to the axle just for the pics, then took it off..so no business about the fasteners :). I use SS braided, Teflon core hydraulic lines zip tied to the gear legs to connect the fittings at the gear leg shoulder to the ski cylinder.
John
Attachments
Ski mounting set up.
Ski mounting set up.
Front cable attached to lower engine mount tang.
Front cable attached to lower engine mount tang.
Rear cable attachment to float fitting.
Rear cable attachment to float fitting.
Right side of pump
Right side of pump
Left side of pump.
Left side of pump.
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mdpesky
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Re: Looking for correct drawings for AWB 2500 Skis

Post by mdpesky »

Howard

The fellow I bought my Ski's from in Calgary Alberta has a spare set of Ski Axles, contact me by email: Markp@Rotech.ca for his contact info.

Roesbury, thanks for the advice on lever force, based on that we decided to install the bump on the right side of the tunnel to the floor in front of the co-pilots seat. It does infringe on the co-pilots foot room but this compromise seems worth it when you look at trying to get as long a lever as you can without hitting the underside of the dash! In this case we'll be about 12" lever total height from pivot point.

We opted out of mounting it in front of the rear seat(behind fuel selector valve) like Johns because we didn't want to interfere with hauling our Elan Ski-Doo in the back, as you can imagine, we need all the cargo space we can muster! That said, the pump will be mounted to still allow the seats to be slid "forward" on the tracks far enough to be able to disengage the front seat supports from the seat rail, this allows you to then disconnect the seats from the rails without having to slide them all the way back until the front seat catches release, allowing you to get the seats in and out to make room for putting large objects into the cabin like Elan Ski-Doos, sleighs, stoves and various other bulky items, an important consideration for our mission use of the aircraft(flying with no seats sitting on the hood of a Ski-Doo is no fun!!! Yuk, Yuk)...

Once completed we can post some pictures. Thanks John for those you posted.

Mark
MDPesky:1954 C-170B/C145/Horton Stol, 1960 C-182C/520ci/Sportsman/Vortex/Wing-X/Alaskan Bush Wheel/Atlee Dodge/Ext-bag/Belly-Pod, 2013 Zenair CH750/912iS, 1999 Europa Tri-Gear/914 Turbo
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