Buying a new clock

russfarris · Post by **russfarris** » Tue Dec 19, 2006 5:03 am

The original Wittnauer wind-up clock, overhauled six years and 600 hours ago by Century Instruments quit working some months ago. I fly my 170 IFR when conditions require it, so this needs to be addressed. As usual, it's not as simple as it sounds.

I don't want to fool with the wind-up anymore - the vibration in an airplane doesn't seem to do it any good. George a while back suggested a quartz clock from Aircraft Spruce: 10-22812, which looks pretty authentic (I'm kind of a originality freak.) I called them today, and they asked if I was going to use it in a certified airplane. When I said yes, they said it had no PMA or FAA approval, and wouldn't be legal. Well...

I did a little more searching and found a nice looking quartz clock by Mitchell, AC Spruce part no. 10-01214 which is FAA/PMA approved, for the same price, about 90 bucks. It looks even more original the the non-approved clock. The bad news is, AC spruce won't have it in stock until
the first of the year.

The clock first listed was shown as original equipment in later Cessna Piper, ect which AC Spruce says is a mistake - funny, since it looks EXACTLY like the ones I've seen in many airplanes. Since the clock is required equipment for IFR, it does need some approval basis - I'm assuming the Wittnauer had it, since it came back with a yellow overhaul tag from Century. I'll get the Mitchell when it becomes available, so the point is a little moot.

George, what's the story on the 10-22812? Did the manufacturer decide to pull the plug on the FAA/PMA approval for liability? Is it a Chinese clone? It's a minor mystery, but I know you like to look into these things, especially since you recommended an illegal clock to us

Russ Farris

Post by **GAHorn** » Tue Dec 19, 2006 5:35 am

Don't ask ME why the mfr. and the seller of the clock make certain representations or not. Ask THEM. While you're at it, ask them how many of the hour meters they've sold to certificated aircraft owners are FAA-PMA.

My previous recommendations were based upon their previous representations that it was original equipment.
Make certain that when you install your new clock that you also use traceable MS screws to mount it and torque them with a properly calibrated and certified torque wrench.

hilltop170 · Post by **hilltop170** » Tue Dec 19, 2006 5:40 am

Russ- I understand the originality issue but for functionality, especially while IFR, Electronics International makes a very nice digital clock, model SC-5, that does far more than I have been able to figure out so far. All joking aside, I have been impressed with the features such as up and down timers with alarm LIGHTS when set points are reached, and ability to set Zulu 24 hour time. They even have another more-Gucci one, model ASC-5A that reads your Altitude Encoder and displays your current altitude as seen by ATC. That would be nice but I drew the line at semi-Gucci. It's approved, too.

Post by **GAHorn** » Tue Dec 19, 2006 5:59 am

Richard, can you actually hear the alarms over the engine and noise-attentuating headset?

russfarris · Post by **russfarris** » Tue Dec 19, 2006 6:03 am

Well, I'm about to join the elite corps of illegal quartz clock owners.

After looking at my panel overlay, I realized that the cut-out at the seven o'clock position would be empty if I used the Mitchell clock - it's set knob is located inside the instrument panel overlay cutout and would look funky to me. So I'll install George's original recommendation, which he made on the basis of inaccurate information. I have MS screws that can be traced to the original ore mine in Botswana, so I'm well covered there. Also, my inch-pound torque wrench from Harbor Freight Tools has been recently calibrated on a certified torque board so I think I'm OK. Unless you guys think I missed something

Seriously, what I think has happened is the original electric Borg clock was the PMA approved one. The quartz movement look-alike, which we are dealing with here, apparently never jumped through the hoops for certification. I'll take this one up with my IA to make sure he'll sign off on it - otherwise, I have to use the Mitchell. Russ Farris

Post by **GAHorn** » Tue Dec 19, 2006 6:09 am

Are you going to hot-wire it?
When I replaced my clock I purchased a U.S. Navy contract overhauled unit which has been a treasured item in my panel. It has a push-button start/stop, third-hand timer at the 2 o'clock position I had to drill a hole for in the false-panel for the pushbutton. This wind-up clock was standard issue in the old DH-125 I used to fly and I just had to have it, despite the $120 price. 20 jewels, US mov't, but for the life of me I cannot recall the mfr. Came with a yellow tag doc for the overhaul.
There it is to the right of the pilot's yoke.

blueldr · Post by **blueldr** » Tue Dec 19, 2006 6:21 am

Talk about making mountains out of mole hills!!!

russfarris · Post by **russfarris** » Tue Dec 19, 2006 6:25 am

Richard, I considered one of them there fancy clocks, but ruled it out for two reasons - a simple second hand is all I need, since setting a fancy
clock is just another distraction to turn my airplane upside down and second, I'm cheap. 90 bucks sounds better than 200 to 400 dollars.

I'm as much as a stickler (almost) as George for being legal, since both of us depend on aviation for our meal tickets. As many of you guys do.

So, am I being all little over the top on this clock business? For example, for a VFR installation would this be an issue? (Well, since it's hard wired to the electrical system, probably...) Opinions, please...Russ Farris

Post by **GAHorn** » Tue Dec 19, 2006 6:27 am

blueldr wrote:Talk about making mountains out of mole hills!!!

Now,...let's talk about the technique of how to wind the clock. Do you wind it clockwise, release the stem, reposition your fingers on the stem, and then wind it again clockwise?
Or do you wind it clockwise, then without releasing the stem, wind it counter-clockwise, allowing it to "ratchet" to re-position on the mechanism, then wind it again clockwise?
Do you wind it up fully? Or only partially?
Does it actually run a full 8 days?

(Russ...why don't you email Ole Gar and tell him to send you that Genuine Cessna clock I gave him 3 or 4 years ago that he'll never actually install?) BTW...did I ever tell you about the book I saw on a local airport coffee table that,among many accident stories, described the mid-air accident between your 170 and the DC3?

N1478D · Post by **N1478D** » Tue Dec 19, 2006 6:35 am

gahorn wrote:Are you going to hot-wire it?
When I replaced my clock I purchased a U.S. Navy contract overhauled unit which has been a treasured item in my panel. It has a push-button start/stop, third-hand timer at the 2 o'clock position I had to drill a hole for in the false-panel for the pushbutton. This wind-up clock was standard issue in the old DH-125 I used to fly and I just had to have it, despite the $120 price. 20 jewels, US mov't, but for the life of me I cannot recall the mfr. Came with a yellow tag doc for the overhaul.
There it is to the right of the pilot's yoke.

Anybody can tell by looking at the picture that's a Waltham A13A/L Aircraft Clock! Part Nbr: 400236 Mil-C-6499C and that it was rebuilt by Jon Vleck - Clockmaker in Ozark, Alabama 36360, at 1300 Hwy 231 South!

russfarris · Post by **russfarris** » Tue Dec 19, 2006 6:37 am

Hi Dick, sure it's making mountains out of molehills! Some of us think its kinda fun! You should see some of the discussions on what is authentic for Studebaker Avantis.

George, per what you suggested a few years ago, I plan on wiring the clock (whatever it ends being) to the battery side of the master solenoid,
with a 1 amp in-line fuse. That's a cool sounding clock you have, but every wind-up clock I ever had in my Stinson and 170 croaked. A local
watchmaker wanted 200 bucks to fix mine. Russ Farris

russfarris · Post by **russfarris** » Tue Dec 19, 2006 6:51 am

Thanks George, I'll e-mail Ole Gar - he thinks I'm crazy to fly a 170 in the clouds anyway!

I have a 1959 book called "Plane Crashes!" which details 43A's close encounter with a DC-3 very well; was that the one? It has the twisted wreckage of a DC-2 or 3 on the dust cover. The weird thing is, I had this book and knew all about this accident long before I bought my 170. I remember at the time thinking how cool it would be if it was the same airplane, but I never made the connection till a Google search late one night...Russ Farris

Post by **GAHorn** » Tue Dec 19, 2006 7:09 am

You know, Spruce is pretty blatant in their promotion of the clock I first suggested to you...their website claims it's original equip. in Cessna, Beech, Piper, etc. for $93.50 I think I'd still go with that.
http://aircraftspruce.com/catalog/inpag ... zclock.php
Anyway.... just so you know....I'm not impressed with the Mitchell instruments. Their needles look like cheap plastic when you see them in real life.
Davtron also offers a nice clock, Spruce PN 10-00459, for $189. FAA-PMA (according to Spruce.)
http://aircraftspruce.com/catalog/pspag ... clocks.php

Post by **GAHorn** » Tue Dec 19, 2006 7:17 am

N1478D wrote:Anybody can tell by looking at the picture that's a Waltham A13A/L Aircraft Clock! Part Nbr: 400236 Mil-C-6499C and it was rebuilt by Jon Vleck - Clockmaker in Ozark, Alabama 36360, at 1300 Hwy 231 South!

Wow! That's RIGHT! Man! Joe you are a real farrr....uh....I mean a real smart feller!

(I'da had to wait until I got home to find my yellow tag before I could have come up with that info. You ain't gonna tell 'em where I found out about the guy that had several dozen of 'em for sale are you???)

(Inside joke, everyone. Several years ago Joe was looking for a clock and I put him onto a guy I'd found had a whole bunch of them with fresh Navy Overhaul tags. Not long thereafter I needed one myself. I'd completely forgotten about Joe's.)

BTW, Joe...did you know the Navy had paid $618 apiece for those overhauls? I wonder what they'd paid originally for the clocks themselves. Either we've got a couple of really fine timepieces, or the Navy has got too much money to spend, or both!

N1478D · Post by **N1478D** » Tue Dec 19, 2006 7:23 am

Not too smart! It was so funny with the really small picture, you can hardly see the clock, I tore up my bedroom trying to find the info that came with the clock. Now it's late at night and I have to put all of the log books back up!

I still feel grateful that you gave me that info George. I really enjoy that clock. It looks better in a 170 panel than that picture represents.

Wow! Ol Jon the clockmaker did real well didn't he! They are a treasure. It fits in with my panel very well also, sure looks the time period.