AvCon, Avcon, Av-con, ...a con?

A place to relax and discuss flying topics.

Moderators: GAHorn, Karl Towle, Bruce Fenstermacher

Re: AvCon, Avcon, Av-con, ...a con?

Postby marathonrunner » Wed Nov 14, 2018 2:57 pm

Hey Pokey great to see some not so common sense prevail. I’m guessing the Williams have to be close to their 80’s. I’m surprised you got a response. Most of these older STC’s are approaching 50 years or more old. Some have expired due to the owners passing and next of kin had no interest or knowledge of what to do. I know the FAA is starting to grapple with this issue now. The Sportsman STOL cuff almost went the route of not even becoming an STC from what I gather. We have an STC and are going to pass it on to our grandkids so it can continue to be a viable STC for decades to come.

Not all STC holders are irresponsible but after nearly half a century they may not have parts or even the facility or ability to support their STC after decades.
It's not done till it's overdone
marathonrunner
 
Posts: 449
Joined: Mon Dec 13, 2010 3:49 am

Re: AvCon, Avcon, Av-con, ...a con?

Postby GAHorn » Wed Nov 14, 2018 6:14 pm

marathonrunner wrote:Okay. I’m about to just dump my membership with this organization. I put an Avon conversion in my 170 from Bob Williams about 20 or so years ago. I got it from a plane that had a landing incident. I spoke with him many times and he was quite cordial. My mount was tweaked and needed repair so I sent it to him and it was repaired and returned in a prompt manner and for a fair price.

Seems most posts here folks want stuff for cost less 20 percent. Sorry guys, your hobby isn’t your mechanics hobby. He or she have to make a living, pay bills and support themselves and family. I have responded to many members who were looking for parts and I have found them, gotten them from the salvage yard, packaged them all for free and without exception, every member has changed course and not gotten the parts due to costs of shipping from Alaska. I have a shelf of parts I could damn near build a 170 with.

If you think it is so easy to get and maintain an STC for a dwindling fleet. Jump in...the water is warm


Joel, I hope that first comment is only a comment of frustration... and not a serious problem with the fact this thread is a forum about the experiences others have had with the Williams. In an excerpt from an earlier post:

gahorn wrote:There's no intent to cause harm,.... ... I realize you may have an Avcon Lycoming conversion and may feel defensive perhaps, but if you have positive relations with the Williams feel free to contradict rumor with your experience....


That is what forums are good-for... sharing experiences, information and help... for-which the poor experiences (as well as your good one) are useful.

As for folks that order parts from you and then fail to pay... that's despicable IMO. I hope by now you inform such people that you ship COD and warn them to check freight prices before you put out efforts for them. (And your contributions are some of the best ones read here.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight.
An originality nut (mostly) for the right reasons. ;)
User avatar
GAHorn
 
Posts: 19576
Joined: Fri Apr 12, 2002 8:45 pm
Location: Spicewood (Austin), Texas

Re: AvCon, Avcon, Av-con, ...a con?

Postby marathonrunner » Wed Nov 14, 2018 7:36 pm

George yes it was out of frustration. Let’s just say I’ve gotten old enough to not want to deal with the frugal individuals who seem to think they are being taken advantage of just because they have to spend money on their aircraft. Some of these same folks have no issue getting their autos worked on for far more per hour as well as parts the auto places won’t let you bring in.

I’ve gotten to the point I just locate the parts and give them the contact information so they can haggle with the yards themselves. I have never made or tried to make a dime by helping out and it has bitten me in the butt several times

I posted to Old Pokeys second post. It is difficult to obtain and maintain STC’s. I know this from personal experience. I’ll email you directly about some very startling information I discovered recently when adding the slant tail 172series through the P models to our existing STC for Aerocet 2200 floats on the 170 and straight tail 172 series. Not real sure how the information will be taken but it is serious stuff

Cheers
It's not done till it's overdone
marathonrunner
 
Posts: 449
Joined: Mon Dec 13, 2010 3:49 am

Re: AvCon, Avcon, Av-con, ...a con?

Postby 170C » Wed Nov 14, 2018 11:16 pm

Unfortunately I am not very well versed in the details of STC's. Someone comes up with a good idea, spends their time and money developing the product and does what is required by the FAA and ends up with an STC. I suppose some STC's are paperwork only while others include, or can include, parts, etc. I don't know if there is any FAA requirement for an STC holder to keep that STC active. On the one hand if you do all the work to develop the STC, then you should be permitted to continue it or if you choose not to do so you may can just deep six it. However, those folks who have obtained an STC from you, and/or parts, likely look to you to still have those parts available from now own. It seems that there should be protection for both parties. I'm sure you can sell me your STC and relieve yourself of any obligation or liability connected to it. Then we would hope the new owner would support it until such time as he no longer wishes to do so. One would hope a club or other owners group would be offered an opportunity to purchase the STC if it would benefit them. Someone can enlighten me on this if desired. Thanks for your input.
OLE POKEY
170C
Director:
2012-2018
User avatar
170C
 
Posts: 3184
Joined: Tue May 06, 2003 11:59 am
Location: Murfreesboro, TN

Re: AvCon, Avcon, Av-con, ...a con?

Postby GAHorn » Thu Nov 15, 2018 7:31 pm

Frank, there's a difference between owning an STC (which is only FAA approval to modify IAW the instructs) …. versus owning an STC and also selling the parts necessary to perform that mod. If the parts are specially mfr'd and available from the STC-holder, the seller must also provide an approval basis for those parts (such as FAA-PMA...or perhaps the mod only requires standard AN hardware, in which case the seller only supplied them as a courtesy. C-Mods fuel drain mod to the selector valve comes to mind.)
I've seen those FAA-PMA Saf-Air valves simply installed and logbook entry claiming "minor alteration", which my IA thinks is fine on my 172. But I got the idea from the C-Mods STC I had purchased previously for my 170B.
If an STC is only paperwork (approval basis for the mod) then the purchaser has to perform the mod according the STC instructions and find the parts on his own from the list of approved parts the STC specifies. That STC developer has no legal obligation to support the STC beyond that. He can die, move, quit, or other... and anyone who purchased that STC still has to follow the ICA's which are applicable to maintain the airworthiness of the mod.

An example of an "orphaned" STC is the belt-driven vacuum pumps some 170s have installed under STC. The particular pumps utilized are no longer mfr'd/supported by the pump-OEM. There are no parts available (unless someone just happens to have some NOS sitting around and you're lucky enough to run into that person.)
Otherwise, when the pump dies.... the only alternative is to return the airplane to another approved condition (remove the mod and go back to some other approved system).... or make your own parts under the "owner produced parts" rule. Most owners are unable to perform work of that level of sophistication. The STC is no longer applicable and the airplane is no longer considered airworthy until that problem is resolved. This last situation is where "disappearing STC owners" become a problem. The STC is "property" (intellectual) and passes to the estate of a deceased owner. If the heirs are not into airplanes and have no idea what that authorization letter from the "FFA or FAA" or whoever they think that was...and they toss it in the trash.... then it's now an "orphan STC". You can keep operating with it as long as it works...otherwise you must maintain it as the STC or FARs require... or remove it. Or get your own basis of approval from FAA.

Think of an STC as "intellectual property" that you buy a license-to-use from the developer. As long as no future need for support is req'd...you're golden.
But don't expect anyone to help you maintain your Univac computer and be prepared to go back to using your trusty old abacus.
In other words, … think about it before modifying your airplane with an STC that may become unsupported. Sometimes "original" is for the "right reasons".
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight.
An originality nut (mostly) for the right reasons. ;)
User avatar
GAHorn
 
Posts: 19576
Joined: Fri Apr 12, 2002 8:45 pm
Location: Spicewood (Austin), Texas

Re: AvCon, Avcon, Av-con, ...a con?

Postby marathonrunner » Mon Nov 19, 2018 4:05 pm

In other words, … think about it before modifying your airplane with an STC that may become unsupported. Sometimes "original" is for the "right reasons".

Unfortunately, OEM’s of aircraft like auto manufacturers, do not support their products indefinitely. Hence salvage yards and manufacturers who make PMA parts and STC’s
Last edited by marathonrunner on Wed Nov 21, 2018 5:08 pm, edited 1 time in total.
It's not done till it's overdone
marathonrunner
 
Posts: 449
Joined: Mon Dec 13, 2010 3:49 am

Re: AvCon, Avcon, Av-con, ...a con?

Postby c170b53 » Mon Nov 19, 2018 8:29 pm

Well said last two posts. I have a Doyn and rare can be a bad thing. Then again I could hang a PT 6 on there, call it a Bush conversion and I would’nt be lying
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
User avatar
c170b53
 
Posts: 2234
Joined: Mon Apr 22, 2002 8:01 pm
Location: Vancouver B.C.

Re: AvCon, Avcon, Av-con, ...a con?

Postby marathonrunner » Mon Nov 19, 2018 9:40 pm

Jim, is your Doyne the O 360?
It's not done till it's overdone
marathonrunner
 
Posts: 449
Joined: Mon Dec 13, 2010 3:49 am

Re: AvCon, Avcon, Av-con, ...a con?

Postby c170b53 » Tue Nov 20, 2018 8:03 pm

No it’s a poor man’s 0-320 which ironically costs a heck of a lot for the performance gain compared to the 0-360,
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
User avatar
c170b53
 
Posts: 2234
Joined: Mon Apr 22, 2002 8:01 pm
Location: Vancouver B.C.

Re: AvCon, Avcon, Av-con, ...a con?

Postby Mayday » Thu Jun 13, 2019 6:10 pm

I just found this thread and figured I'd update with my recent experience with Bob Williams. Last fall (2018) I purchased the STC paperwork package for the O-360 conversion. Note: I own a C175, not a 170, so I have a stepped firewall. Besides a few parts like the mount/air-box, the conversion is identical. I spent a good amount of time researching and gathering parts, bought a run-out 0-360 which I overhauled and when I was ready I did the conversion which took me approximately 8-10 days worth of labor to complete (most of the labor was building baffling and installing a CGR-30P engine monitor). Bob charged $1250 for the STC, and due to being diligent in hunting for deals and performing the labor myself, I ended up completing the conversion for almost exactly $20K, an amazing price when you factor in a 0 SMOH 0-360 and the CGR-30P (premium) engine monitor. The lack of support from Bob/Avcon/Bush is a non-issue in my mind, if you can get your hands on an engine mount and airbox, the rest of the parts are easily "owner produced" or can be substituted with more modern components. When comparing prices, if you're willing to put in some work yourself the Avcon route in my mind is by far the most cost effective option.
Mayday
 
Posts: 13
Joined: Sun Apr 27, 2014 8:05 pm

Re: AvCon, Avcon, Av-con, ...a con?

Postby c170b53 » Fri Jun 14, 2019 4:07 pm

Could you possibly break down the numbers for clarity so that others can quesstimate their potential outlay. I say this because the cost depends on what is required, ie I'm not an NDT guy so I couldn't NDT the mount for its certification. I'd have to send that out to an approved shop. My mount cost me 1500 for its recertification ( paint strip, NDT, dimensional check and repaint). Your prop, did you find one that was already overhauled ? They are no longer cheap. How about the governor was it overhauled ? I think you must have found some solid deals out there, of course your time to accumulate and rework the components obviously saved you thousands. Good that you could get her done !
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
User avatar
c170b53
 
Posts: 2234
Joined: Mon Apr 22, 2002 8:01 pm
Location: Vancouver B.C.

Re: AvCon, Avcon, Av-con, ...a con?

Postby Mayday » Fri Jun 14, 2019 7:27 pm

c170b53 wrote:Could you possibly break down the numbers for clarity so that others can quesstimate their potential outlay. I say this because the cost depends on what is required, ie I'm not an NDT guy so I couldn't NDT the mount for its certification. I'd have to send that out to an approved shop. My mount cost me 1500 for its recertification ( paint strip, NDT, dimensional check and repaint). Your prop, did you find one that was already overhauled ? They are no longer cheap. How about the governor was it overhauled ? I think you must have found some solid deals out there, of course your time to accumulate and rework the components obviously saved you thousands. Good that you could get her done !


Thanks, I really should sit down and put together a write-up from my experience doing the conversion. I will do my best to itemize my costs, I do remember when I totaled it out when I was done I was at somewhere around $20,500 at the end of the project.

STC Paperwork: $1,250
Engine mount, Airbox and exhaust (sourced from air salvage yard): $2,500
Purchasing run out 0-360A1A and overhaul costs: $14,000.
Sensenich FP Prop: $900
CGR-30P (Found second hand but new in box for $1,800, spend about $400 to send back to EI for reconfigure): $2,200
Baffling/oil cooler aluminum kit (needed lots of assembly):$300
Random lines, fittings, cables, mounts, electrical (voltage regulator) and and extra stuff: $3,500(ish)

Total for all this ran me a little under 25k. I also purchased a spinner for $450ish bucks but ended up finding another spinner that worked better for free.

I sold off the core GO-300 I removed for $3,500 and a handful of other removed parts for another $500ish bucks. I still have the prop off that engine I will probably try and offload here at some point.

So after expenses and recouping some money from the sale of the removed parts it came in at just a hair over $20K. You can also see this is using a fixed pitch prop, I couldn't justify the relatively minor performance difference for the cost of purchasing and maintaining a constant speed prop especially considering 90% of my flights are under 45mins and its easy to put one on in the future if I really want. I did not send out the accessories as the mags only have something like 300 hours on them and the starter/alternator were both less than 500. I really shopped hard for deals, calling every salvage yard I could find over and over again for a few months to finally get the parts needed. The airbox ended up needing to have the bell-mouth cut off and rebuilt. All in all, this project probably took me close to two years to complete from the time I started researching and souring parts to the time the conversion was done and flying. The actual touch labor for the conversion itself went pretty quick, its not a difficult job and as I mentioned earlier probably the most time consuming part was building the baffling and installing the engine monitor and its components. It took some enginuity to cut the exhaust hole in the right place in the lower cowl as the instructions in the STC were....lacking and would have resulted in the center of the hole being off over an inch so I used a plumbob and a laser level. I couldn't be happier with the end result, although it was really almost an even trade performance wise (GO-300 is 175HP), the prop I'm running now is a bit more of a climb prop and I regularly see 1500+FPM climbs with myself and 30 gals of fuel. The main reason I did the conversion was because my GO-300 was in desperate need of an overhaul and parts availability made that near impossible, at the end of the day the cost difference between overhauling that GO-300 and doing the whole engine conversion was probably less than $5k.
Mayday
 
Posts: 13
Joined: Sun Apr 27, 2014 8:05 pm

Re: AvCon, Avcon, Av-con, ...a con?

Postby c170b53 » Sat Jun 15, 2019 2:50 am

Ah... I thought you might be running a fixed pitch. C/S and especially governors have really jumped in cost recently. Again nice to see it works for you and our friend Down Under.
Jim McIntosh..
1953 C170B S/N 25656
02 K1200RS
User avatar
c170b53
 
Posts: 2234
Joined: Mon Apr 22, 2002 8:01 pm
Location: Vancouver B.C.

Re: AvCon, Avcon, Av-con, ...a con?

Postby Mayday » Wed Jun 26, 2019 5:53 pm

c170b53 wrote:Ah... I thought you might be running a fixed pitch. C/S and especially governors have really jumped in cost recently. Again nice to see it works for you and our friend Down Under.


Yeah, although I am confident I could find an airworthy C/S prop and governor for this thing in the $5k range if I really wanted. I really don't know if it would be worth it honestly, in fact I am debating putting on one of the Catto 84" fixed pitch props (I would like to get rid of the rpm restriction of the aluminum prop). 90+% of my flights are under 45 mins, the constant speed sensenich I have on there now gets me out of the shortest strip I use (1,000 ft) no problem even with a passenger and a tank of gas while cruising about 125mph around 8.5-9gph. If I was hauling cargo out of short strips in the mountains then yeah, a C/S prop might justify itself a little more, but the simplicity, ease of maintenance and cost all pushed me towards the FP.
Mayday
 
Posts: 13
Joined: Sun Apr 27, 2014 8:05 pm

Re: AvCon, Avcon, Av-con, ...a con?

Postby GAHorn » Wed Jun 26, 2019 6:11 pm

Mayday wrote:... the constant speed sensenich I have on there now ...


I’ll bet you MEANT to write: “the fixed pitch Sensenich I have on there now”...... :?:
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight.
An originality nut (mostly) for the right reasons. ;)
User avatar
GAHorn
 
Posts: 19576
Joined: Fri Apr 12, 2002 8:45 pm
Location: Spicewood (Austin), Texas

PreviousNext

Return to The Pilot Lounge

Who is online

Users browsing this forum: No registered users and 12 guests