The International Cessna 170 Association

I decided to go with the McFarlane step. Since it's streamlined, the step portion is wider, and I figure the airfoil shape should be good for a couple of extra knots.... But it didn't come with any instructions or drawings, and I can't find anything in the IPC. Does anyone have a diagram of how the step is supposed to attach? TIA.

The rivets (3-4) only attach the piece of aluminum (?) that is a part of the step, which is about 3-4 inches square, to the exterior of the skin. The real strength is the bolt in the top of the step , which is up inside the floor area, and is secured to one of the seat belt attach bolts. This could vary I suppose. This is how mine is secured, but mine is a converted C-172 so the factory 170 could be slightly different.

On mine the upper bolt goes thru the seat track rail, not the seat belt attach.

There are 6 rivets, 3 of which go through a stringer on the inside of the skin. Often times people use structural screws in place of the rivets as some of them are hard to get a bucking bar on.

Tim

ps as an old fat guy I can tell you that the pilots side step is good to 265 pounds, I test it as often as I can.

Dallas170 wrote:I decided to go with the McFarlane step. Since it's streamlined, the step portion is wider, and I figure the airfoil shape should be good for a couple of extra knots.... But it didn't come with any instructions or drawings, and I can't find anything in the IPC. Does anyone have a diagram of how the step is supposed to attach? TIA.

For increased speed you must paint it RED. (And if you wish to avoid flying out-of-trim you'll have to do both sides.)

Frank, my step is installed using SIX rivets at the lower skin. I have also observed this on numerous others. The (never-to-be-in-error) IPC also appears to have six.

How many other owners can report the number of rivets holding their steps?

Now I have to go back and look to see for sure if mine has 4 or 6 rivets, but again its a conversion so it shouldn't be used as a guide for the correct number.

For accuracy sake, mine also has six rivets vs the 4 I mistakenly stated earlier.
Also the bolt goes thru the seat rail vs the seat belt bracket.

I missed an opportunity for a picture as I saw a flat teardrop style pad added (welded) to an original style step on a 170 at a fly in on Sunday. Functional but just didn't look right!

gahorn wrote:

Dallas170 wrote:I decided to go with the McFarlane step. Since it's streamlined, the step portion is wider, and I figure the airfoil shape should be good for a couple of extra knots.... But it didn't come with any instructions or drawings, and I can't find anything in the IPC. Does anyone have a diagram of how the step is supposed to attach? TIA.

For increased speed you must paint it RED. (And if you wish to avoid flying out-of-trim you'll have to do both sides.)

Frank, my step is installed using SIX rivets at the lower skin. I have also observed this on numerous others. The (never-to-be-in-error) IPC also appears to have six.

How many other owners can report the number of rivets holding their steps?

Will do on the red paint. I couldn't find the step flipping through my copy of the IPC. Do you have a page number?

Dallas170 wrote:

gahorn wrote:

Dallas170 wrote:I decided to go with the McFarlane step. Since it's streamlined, the step portion is wider, and I figure the airfoil shape should be good for a couple of extra knots.... But it didn't come with any instructions or drawings, and I can't find anything in the IPC. Does anyone have a diagram of how the step is supposed to attach? TIA.

For increased speed you must paint it RED. (And if you wish to avoid flying out-of-trim you'll have to do both sides.)

Frank, my step is installed using SIX rivets at the lower skin. I have also observed this on numerous others. The (never-to-be-in-error) IPC also appears to have six.

How many other owners can report the number of rivets holding their steps?

Will do on the red paint. I couldn't find the step flipping through my copy of the IPC. Do you have a page number?

Reality-check: The commercial specified paint scheme was to paint the steps "Gull Grey". My own are so painted. (I think it was to help keep the nose down to keep the red plane from climbing so steeply.,,, it definitely seems to be working...)

I checked this am and my steps are secured by only 4 rivets. I suspect that is because its a conversion as most 170's seem to have 6 rivets. The rivets attache a 2 1/2 " X 2 1/2" section of aluminum to the aircraft skin.

Frank, ...as you know, the 172 had a step on the main gear-leg. So I imagine your airplane used a 170 step? (Or perhaps another type?) You might keep an eye on the rivets to make sure they don't begin to tear out a hole in the bottom skins. Adding a couple rivets shouldn't be too difficult if necessary.

Mind your step!!! Well my pilots step broke today and I was lucky in one way I wasn't hurt. My jeans had a small cut in them as my leg slide down the broken step and a piece of steel sticking out acted as a knife. My steps get a frequent inspection as the leading edge of the step often gets sand blasted and I paint it to stop corrosion. HOWEVER , this corroded from the inside out. I will be buying a Mc Farland step at about $365.00 US . The new one is believe is filled with oil to stop corrosion. I really caught by surprise on this one .
Some genius has used cherry max rivets [ 6 of] to attach the old step to the fuselage skin . He could have used nails , they would have been better.

I'm getting so heavy I worry about this when I board.... gotta get on the Fenstermacher-Diet....

Ok , Bruce ,you had better step in and give the aviation world this diet [life style] . My wife could use this.[to help me] .