TAIL NAV

How to keep the Cessna 170 flying and airworthy.

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william halford
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TAIL NAV

Post by william halford »

ANYBODY HAVE A GOOD P/N FOR A TAIL NAV FOR A 170A.
MY PARTS MANNUAL JUST SAYS A SINGLE ELEMENT..170MB
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N1478D
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Post by N1478D »

There are several parts, I have purchased a few and can research my receipts for you. Which ones are you interested in? There is the Grimes light socket assembly, and the two larger halves that form with the rudder, and then a few smaller parts assembled to that.
Joe
51 C170A
Grand Prairie, TX
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GAHorn
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Post by GAHorn »

Both Whelen and Grimes make tail Nav lamp sockets/lenses and they can be found at Spruce 877/477-7823 or at WagAero (.com).
If you're looking for the correct bulb # however, it's a GE 1777 (but if you don't tell the FAA, a standard auto backup lamp will work just fine (GE 1156 from Wal Mart or AutoZone, etc. )
william halford
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Post by william halford »

I CLOSED THE HANGER DOORS AND TRYED THE 1156, BUT THE BASE WAS TOO LARGE. I DO NOT UNDERSTAND WHY THAT IS . BUT THEN AGAIN THE SIMPLEST PROBLEMS SEEM TO BE THE HARDEST. I APPRECIATE ALL THE HELP..170MB
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N1478D
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Post by N1478D »

gahorn wrote:Both Whelen and Grimes make tail Nav lamp sockets/lenses and they can be found at Spruce 877/477-7823 or at WagAero (.com).
If you're looking for the correct bulb # however, it's a GE 1777 (but if you don't tell the FAA, a standard auto backup lamp will work just fine (GE 1156 from Wal Mart or AutoZone, etc. )
In an attempt to replace the tail nav light on the trailing edge of the rudder, ordered Aricraft Spruces Grimes Early Model C Model B-1943-4 P/N 11-07200 (new surplus) $110.95 page 420. Hope they take it back. It must be for something the size of a DC-3, nice though. :?

My old Grimes unit that I would like to replace only has part of the part number remaining - 3510 I think, it's very hard to read. Anybody know the part number and if it is available?
Joe
51 C170A
Grand Prairie, TX
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Bruce Fenstermacher
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Post by Bruce Fenstermacher »

gahorn wrote: If you're looking for the correct bulb # however, it's a GE 1777 (but if you don't tell the FAA, a standard auto backup lamp will work just fine (GE 1156 from Wal Mart or AutoZone, etc. )
George while a 1156 will work there may be a significant difference in wattage between it and the correct bulb.

I once was servicing/repairing a Grimes rotating beacon. Someone had figured a way to get a 1157 bulb to fit the socket. Problem was it was using both elements of the 1157 and drawing 5 amps, twice the amperage of the standard bulb. I seem to remember measuring the 1156 and the correct bulb which may or may not have been a GE1777 and finding the difference to be less than the 1157 but not as low as the correct bulb.

My point is just because it fits doesn't mean you want to use it. If you replace your rotating beacon and 3 nav lights with a bulb that uses just a bit more amperage it all adds up. If your working with a 12 or even 20 amp system there isn't much to spare.

I do like the price of the 1156 over any aviation bulb though. 8)
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N1478D
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Post by N1478D »

Just to make sure that the needed information isn't overlooked, the part is the taillamp assembly, not the bulb. Any help would be appreciated.
Joe
51 C170A
Grand Prairie, TX
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3993v
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tail nav

Post by 3993v »

The light assembly-tail cessna part number 0433006 on page 24 item number 29 of the A model parts catalog is available from cessna. It has a new part number of c622001-0102. iwantcessnaparts.com shows this is in stock for 95.34. nick cushman
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GAHorn
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Post by GAHorn »

The original PN 0433006-3 (a GE 1777) has been superceded by a standard GE-93 which is a common automotive bulb with a smaller glass-dome than the 1156, which is an automotive back-up lamp.
Bruce, the nav lights are on a different circuit than the beacon (or should be) so that shouldn't be a concern. The 1156 is rated at 12.8 volts, 2.1A, and 32 CP (candlepower). The 1777 bulb is rated at 12.8 volts, 1.52A, and 26CP, while the latest spec, the 93 bulb now specified by Cessna for this application is rated at 12.8 volts, 1.04A, and 15CP. (I don't know how they got the FAA to sign off on a bulb that puts out reduced illumination.) The nav light circuit should be capable and protected by a 10A circuit limiter (fuse or CB), so the max load should never exceed 6-7A even with an 1156 bulb.
An interesting side-note is that the original 1777 bulb only had a life expectancy of 400 hours, while the 1156 is expected to last 1200 hours, and the 93 is rated at 700 hours expectancy.

If the 1156 doesn't fit, it's possible that the socket has been changed. Some tail nav light assy's (in later aircraft, not the 170) were set up to accept a smaller-base bulb. It's possible that type socket has been substituted for the original. An example of this situation is the 3-light strobe system which Whelen markets. It will not accept the original size bulbs.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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GAHorn
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Post by GAHorn »

N1478D wrote:Just to make sure that the needed information isn't overlooked, the part is the taillamp assembly, not the bulb. Any help would be appreciated.
Joe, the original part number was 0433006, but it has been superceded by C622001-0102 LIGHT ASSY
(List Price: $ 93.47) Stock Available $ 93.47 (EA) available from cessnaparts.com (Hill aircraft).

OR....if you talk nice, and suck up......I can go out to the hangar and get one of the TIC170A used spares and ship it to you. :wink:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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N1478D
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Post by N1478D »

OH GEE, MAN, ok, . . . . ummmmm, George that sure is a pretty airplane you got sitting there!
Joe
51 C170A
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GAHorn
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Post by GAHorn »

AWWWRRIIIIGGGHHHTTTTY THENNNNN!!!!! You want one in blue, grey, green, red....or does it matter? :wink:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Bruce Fenstermacher
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Post by Bruce Fenstermacher »

gahorn wrote:Bruce, the nav lights are on a different circuit than the beacon (or should be) so that shouldn't be a concern. ...
The nav light circuit should be capable and protected by a 10A circuit limiter (fuse or CB),.....
The key word here is SHOULD. My A model should have no dihedral, small flaps and an unbalanced elevator. :wink:

George that info on the bulbs is great info. Dealing with a 20 amp and now a 25 amp system every little bit helps. What I think your info says is I can replace my 3 GE1777 bulbs which total 4.56 amps with 3 GE93 bulb which draws a total of 3.12 amps which is 1.44 amps less draw.

When your aircraft electrical configuration is maxed out as mine is 1.44 amps saving can be significant.
CAUTION - My forum posts may be worth what you paid for them!

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GAHorn
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Post by GAHorn »

Well, Bruce....the plot thickens.
The 1777 bulb is not approved for the navigation wing-tips. The 1777 is a clear, glass domed bulb intended for tail navigation lights.
The wingtip lamps are actually a mirrored bulb.....they have a half-domed internally-mirrored reflective surface. Even more confusing....such bulbs come in two different basic versions...and can be numbered by 3 or 4 different PN's depending upon their manufacturer.

BUT.....keeping in mind that Whelen, Grimes, Universal, Cessna and GE all may use different PN's for the same mil-spec bulb.....here's some info that may help one decide:
The original spec for the 170 was for a 14 volt 21 Watt (1.5A) lamp. This is commonly known as the Grimes 1512 bulb (and also once shared the same PN with Cessna, although Cessna has superceded or no longer recognizes that number.)
The FAA uprated their visiblilty requirements/regulations in the late '70's and subsequent aircraft specified a 14 volt 26 Watt (1.85A) bulb with the same internally mirrored reflector. This is most commonly known as the A-7512-12 bulb (although Whelen PN is W1290-14).
The later 26 Watt bulb will physically fit into the earlier 1512 socket in our wingtips, but they are pulling more ampereage (if you're worried about that small amount....about .7A for two bulbs.)
The higher wattage bulbs put out a bit more light, but my reference tables don't enumerate that in these pn's. Both PN's are rated at 300 hrs. life.
There is another internally mirrored lamp/bulb known as the A- 7079B (with or without the preceding "A") but it is NOT intended for the nav lights (and probably wouldn't fit anyway). It is a larger globe on that bulb. But I mention it because the nav lamps (1512/7512-12) may fit into the rotating BEACONS that the 7079B bulb was actually designed for. Unfortunately, they do not put out the same light, as the 7079B was typically rated at 40 Watts,....but if you're calculating current demand on a limited circuit.... :wink:

Now, not to muddy the water.....but.....
...if you call Cessna they'll likely tell you most of these numbers are no longer valid and that (for example) the nav lamp is actually now a PN 900328-06 (superceding the 0423006-6) and that you must first convert your wingtip to accept Service Kit A-1285G12 or A-1285R12, and THEN you can fit the correct bulb into your navigation wingtip. Don't fall for it.
As near as I can determine (visions of Jack Nicholson again) ...."Heeres the Deeal...." Grimes made the original wingtip fixtures by the zillions during WW-2 and Cessna bought a bunch of surplus stuff to make airplanes out of. (a major reason so many of the original gyros found in our airplanes were made by Tennstedt Division of General Motors, mfr'd under a gov't contract.)
Grimes quit makin' 'em and Whelen started making identical replacements under a Whelen PN. (Care to guess? Yep. W-1285.) So when Cessna had to repair/replace fixtures they had to use a new part numbering system....their fix being a Whelen 1285 part with either a green (G) or red (R) lens.....and then designated according to the aircraft system voltage (12) or (24)....hence their Alteration to Kit A-1285G12 or A-1285R12 part numbers.
Being such perfectionists...they could no longer supply a Grimes bulb (1512) with the older 21 Watt rating for aircraft needing the newer 26 watt Grimes 7512-14....and in any case, with their attentive/compulsive disorder, they couldn't substitute a Grimes part number for a Whelen fixture so they superceded their inventory of identical bulbs with Whelen W1290-14 part numbers. Ooops. Cessna found that folks could/would buy those cheaper elsewhere so :idea: they re-numbered their inventory to mask the China/Mexico suppliers of the same basic bulb to Cessna PN 900-328-06. :roll: (keep in mind that other than your choice of wattage, it makes no difference which bulb [1512/7512-12/W-1290] you install in your wingtip!)

For my tail, I like my 50-cent (beats the heck out of $10.50) automotive 1200 hour rated 1156 backup tail lamp and, not being current-limited, my 7512-14 26 Watt wingtip nav lamps.
You can get the nav lights from Aircraft Spruce 877-477-7823, their PN (just what we needed.....yet another Part Number!) 8O ...
Nav lamp (old Grimes PN 1512) 14 volt, 21 Watt = Spruce PN 11-01954 priced at $13.95.
Nav lamp (old PN A-7512-12 or W-1290-14) 14 volt, 26 watt = Spruce PN 11-01964 priced at $13.95.

But...

... finally.....just to give us all a laugh because everyone selling aircraft parts thinks we're stupid....if you order the 26 Watt identical bulb from the same place (Spruce) but use the Grimes/Whelen part number......W-1290-14....you'll get that same bulb for three dollars less....only $10.95.
8O
:?
:roll:
:lol:
:evil:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Bruce Fenstermacher
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Post by Bruce Fenstermacher »

George I'm speechless. 8O

Once again I'm dumbfounded at the wealth of information you have, the fact that you remember you have it but mostly that you can find it when you need it. I KNOW you didn't rattle all that info of the top of your head.

I'm also very grateful that you'll take the time to type it out here. :D
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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