I LOVE Handpropping

[Hank Jarrett]

Re: I LOVE Handpropping

A few minor problems with the system (and I sure hope I am not stomping any Tribe toes here).

First, we need something that fits INSIDE the cowl (which may be the biggest problem, there just isn't enough room in the stock 65 cowl)

Second, we need something that looks a bit more professional (sorry, but that thing really looks like something the kid next door banged out in the garage to start his go-cart)

Third, $1,850 for THAT! You have GOT to be kidding.

Parts of the "concept" look pretty good, but there is NO WAY I would stick that thing in my plane, even IF I could overlook blowing a hole in the top of my nose bowl, putting a ring gear exposed in front of the bowl, letting the ignition leads rub on the shaft on every start (COME ON MAN! AT LEAST TIE THE PLUG LEADS UP OUT OF THE WAY!) and although it DOES look simple to make, I wouldn't touch it, even on HIS plane. The cable to the bent piece of metal to pull the drill trigger and engage the gear looks like something lifted from a booby-trap zip gun. What is the screw driver tip on the drill for? Just in case he wants to take something apart? Anyone check with DeWALT about how they feel about their drill being used for this? Can it take the heat of an engine compartment? What if those two hardware store springs fail to pull the pinion gear back when the engine starts? Starter solenoids have gears specially designed to RELEASE when the ring gear becomes the drive gear and the pinion is being driven. Pump that drill up by spinning it with the engine and I bet you could get a really nice fire when those batteries overload. They are VERY SENSITIVE to charging volts and amps and a DC motor makes a really nice generator.

He actually got a STC on that? Maybe the designer or the people who approved it can chime in and reduce my fears that owner maintenance may be a really bad idea. It may work now, it may work for a while, it may cost you a LOT more than $1,850. I want to see some engineering info!

Hank

And I REALLY want to know who approved it for an STC at the FAA!

[blakecarl]

Re: I LOVE Handpropping

...The Dawn Patrol guys in Kansas City used chain saw engines for a while and I think most have converted to electric drill motors now and use 12 and 18V battery packs to start. I want to figure out a way to use them to start our engines. If a drill motor can start a VW it should be a breeze for a Continental 65. Just got to figure out how to get the torque to the crank without ruining the nose bowl.

Hank

I ran across a system several years ago that uses an electric drill.

[Mark Julicher]

Re: I LOVE Handpropping

22 psi is fine.
Service manual calls for 20 psi on BC12-D Too much pressure gets bouncy and sometimes twitchy, to little pressure gets wiggly squirrely

[runon]

Re: I LOVE Handpropping

I tested the Fuel off to see how long it takes to exhaust all fuel remaining fuel and shut down...... It's a little while, probably 30 seconds or more off idle (about 1000 rpm). It would be nice if there was some sort of mag lanyard, but so far I haven't been able to string something up that would work. Next test will be how much throttle it takes to get over my chocks. I'll get video and post my findings when I do. I'm thinking I'll have tire pressure around 22psi - is this correct?

[Pearson]

Re: I LOVE Handpropping

The propping part is easy, it is everything leading up to it that can get you into trouble.

Right on Marty! It is all the [I]little stuff[I] that can kill you. I always turn my fuel off also. If the throttle is at idle it takes 30 seconds or so to run out of fuel. But at higher settings it runs out in just a few seconds.

[M Towsley]

Re: I LOVE Handpropping

I'll interject here about the fuel 'off' idea. My plane runs for quite awhile with the fuel off. Anything that is going to happen will happen long before the fuel exhausts. Unless, you decide to start on one end of an unobstructed field and at something far above idle. (I know what you are thinking, I have heard the stories and seen the Youtube videos).

My situation is a set of hangars across from me and a fence and other obstructions everywhere else. Mine would not run out of fuel before striking something else.

You have to have a ritual and stick to it. Every time. No deviations and do not rush. The propping part is easy, it is everything leading up to it that can get you into trouble.

[NC43501]

Re: I LOVE Handpropping

The one rule I have always used since I started hand propping airplanes in 1973 is to always TURN OFF THE FUEL VALVE before starting.

Thank you for this. This never occurred to me in all the years I've been hand propping my plane. I feel a bit silly, since it's such a good/simple idea. I always learn something new everytime I'm on this forum. At my airport, there isn't a whole lot of "vintage" aircraft anymore, and much of what I know about my Taylorcraft, I've picked up here.

[senior]

Re: I LOVE Handpropping

Fuel off on start-up is something I also always do to.
With the door also opened right to the boot cowl, which allows you to instantly reach in & adjust throttle, switch mags or switch off if needed!
I also keep a single leather (right) glove in the corner of the windshield for propping.
I never used a glove with the old prop but the one I'm using now seems to be much sharper on the trailing edge.

Re: I LOVE Handpropping

I think we're into semantics here or splitting hairs. If you push or pull on the prop anywhere against the trailing edge, then unless you are using your elbow, something is sticking out on the other side of the prop whether it is your fingertips or part of your palm with the fingers attached on the end. I just went out to my airplane and tried to pull the prop through front or back without touching the trailing edge and I can't do it. I just can't get enough of a grip without part of my hand pulling the trailing edge especially from the backside where the prop blade angles away from you.

Bob,

I have seen folks wrap their fingers around at a knuckle I think that is more precarious than a finger tip against the trailing edge. That's all I meant.

Dave

[n6346m]

Re: I LOVE Handpropping

Hank,
Perhaps someday someone can show me how it's done. I'm not too old to learn something new. However I am just as comfortable propping from the front or the back and for the type of flying I do I just prefer the back, especially when on skis and floats, and besides because you do it with only one hand you only have half as many fingers to lose. Maybe I'm having a problem with the term "wrapping fingers" around the prop. You don't have to have your fingers "wrapped" around the trailing edge to have contact with it with some part of your hand. Even with a perfectly straight hand with all fingers sticking straight out, I still contact the trailing edge with the meaty part of my palm where the knuckles join the palm.

[Hank Jarrett]

Re: I LOVE Handpropping

I have never tried to start from behind, but I can see where it would be difficult to impossible to not wrap your finger tips. From the front I can guarantee you it is NO PROBLEM for me to pull an engine through without wrapping the tips. Compression has never been a issue from a 220 HP radial that was soft as a feather (till it back-fired and ruined a good pair of pants) down through my A-65-8 (which was NEVER a problem) to the NASTIEST engine I ever propped, a short stroked, high compression, tiny propped little VW 1600 that would jump out and bite you in a heart beat. That one required BOTH hands, crossed at the hub and a "flipping" motion where you twisted the prop from close to the hub to get enough spin to get her to fire. Not only that, but the little monster spun BACKWARDS.

I HATED that little piece of junk. It ran great and worked well but I doubt I would EVER hand prop one again, especially with the nice starters you can build or buy for them now. The Dawn Patrol guys in Kansas City used chain saw engines for a while and I think most have converted to electric drill motors now and use 12 and 18V battery packs to start. I want to figure out a way to use them to start our engines. If a drill motor can start a VW it should be a breeze for a Continental 65. Just got to figure out how to get the torque to the crank without ruining the nose bowl.

Hank

By the way, I still use my list to start. It can be a pain, but while I was in the Navy in an E-2 squadron we had a Tech Rep walk into a T-56 prop. I will put up with the problems. It isn't something you forget soon (in my case, not in 40 years).

[taylorcraftbc65]

Re: I LOVE Handpropping

I prop start my BC65 standing in front of my prop, with REALLY HEAVY and HUGE chocks that look like they were used on a DC-3. When I do it, I have about an eighth of an inch worth of three fingers of my left hand, hanging of the trailing edge of the prop. I DON'T power the prop for a long distance, I set it up where I "Prop" it from 11:00 O'clock, to 9:00 O'clock.
Brie

[n6346m]

Re: I LOVE Handpropping

It is possible push (or pull) against the trailing edge of the prop without wrapping your fingers around it.

I think we're into semantics here or splitting hairs. If you push or pull on the prop anywhere against the trailing edge, then unless you are using your elbow, something is sticking out on the other side of the prop whether it is your fingertips or part of your palm with the fingers attached on the end. I just went out to my airplane and tried to pull the prop through front or back without touching the trailing edge and I can't do it. I just can't get enough of a grip without part of my hand pulling the trailing edge especially from the backside where the prop blade angles away from you.

Re: I LOVE Handpropping

It is possible push (or pull) against the trailing edge of the prop without wrapping your fingers around it.

[n6346m]

Re: I LOVE Handpropping

I've been thinking about why some people worry about fingers around the trailing edge of the prop when hand-propping. The only time I can see that it would be a problem is when the engine would kick-back. OUCH !!! That hurts. If you do not have an impulse coupling your magneto timing is advanced and is more prone to kicking back. Impulse couplings not only speed up the magneto they also fire a retarded spark close to TDC and pretty much eliminate kick-back and make the engine easier to start.
That's why when timing an engine you fire the impulse and go back and set the required magneto timing with the impulse coupling disengaged. When I had my A-65 on my L-2, I had a single impulse coupling on the right Bendix mag and I always tried to start on the right mag. If I tried to start on "both" I could usually feel the left mag firing early in my fingers. OUCH !
Due to cost, added complexity, reliability and AD issues, an amazing number airplanes have, and only need, one impulse coupling. That's why they make key-start switches that only energize the right magneto when in the start position and spring back to the "both" position when the key is released.
When starting an engine with a dead battery most people unfamiliar with hand propping usually select the "both" position thinking it will start easier. If they have only a single impulse coupler the mags fight each other with different timing and make starting more difficult and therefore more dangerous. If you find yourself in that situation, be sure that if you have only one impulse coupling to only select that magneto when hand propping.