Noticed that little Red ‘M’ at the bottom left corner of some products’ photos lately?
It’s new - and stands for MARKETPLACE, a free listing service for existing TYC customers to sell ( and buy) new or good-quality used Yak parts and tools to/from each other.
Let’s use this good looking AN-2 brake proportioning valve to explain how it works.
A lot of you have asked me to sell YOUR Yak stuff you have in the hangar on this website, so let's give it a try.
Unlike regular TYC store products, these Marketplace items will always be “Qty 1”.
If you are selling, you can check the TYC Marketplace website tab every day - because as soon as your PU-8 disappears, the item has sold. (We’ll re-list the next day if you have more than one to sell - but never post the same item concurrently to put two vendors in competition )
Email me photos of your clean, serviceable Yak Airframe & engine parts or tools you have for sale, (including one showing the shipment packaging you plan to use.) I’ll include your part’s Zipcode / Country from where it will ship in the webpage description...because TYC doesn’t need to inventory your item here in San Diego.
Next comes the most difficult part - because TYC must determine what is and is not suitable to put up on the site.
We all believe the things we want to monetize have great value but there will be times when TYC decides not to post certain parts. We may ask you more questions about them or request additional photos, but it goes without saying that there will be parts we turn down. Let’s hope we can stay friends when that happens.
Please don’t list parts you wouldn’t want your Wingman to go flying with.
Down to the mechanics of it.
Once you’ve supplied me photos and we have agreed a sale price ( which will include a small commission for TYC ) your item goes live using your photos.
We’ll also agree and document your part’s packaged size and shipping weight at the time of listing so shipping cost (which vary with buyer & seller’s location) can be calculated.
Unlike Facebook, the actual price is posted for all to see. No need to Private Message the seller and get involved in haggling.
Unlike Ebay there’s no listing fee and unlike Barnstormers your Ad doesn’t expire - but if your parts are not selling, we’ll probably be in touch to help.
When a customer purchases your Marketplace item, TYC collects your money from them, (including the cost of shipping to your buyer) and emails you a shipping label.
As soon as the carrier’s tracking information shows your item has been signed for, we’ll call the buyer to confirm they got what they expected- then the same day, send you electronically what is owed. (If you don’t have one already, we recommend you set up a Paypal, Venmo or similar electronic funds account.)
Stepping back from the big picture for a moment, you’ll agree everything about this market of Yak owners trading spare parts is....TINY, compared to other types of plane, or Certified aircraft parts for example.
This will never be big & complex like eBay.
TYC’s role will be to ensure buyers are absolutely clear about what they’re buying - because returns, refunds or credits just aren’t practical on this scale.
So why not just list on eBay?
Two reasons really.
While anyone viewing the site can BUY your item, You can be pretty sure the seller is vetted because, like you, they are an existing TYC customer, so probably a Yak owner - and second, like every transaction over the last three years, I’ll be putting my heart into make sure customers are satisfied!
Want to give it a try?
You’ll be surprised how many Yak fans there are, either one airport over or clear across the world, who need your stuff.
TYC Marketplace, uniting the right Yak people with the right Yak parts.
In preparing this product for easy installation, like other TYC products we wanted to leave only footprints.
Bastardizing your property on a permanent basis so we can save a few bucks in manufacture just isn’t how we roll.
That’s not because we’re in any doubt that you’ll absolutely love the convenience of the Hartwell latch Oil Door , or that you’ll ever want to go back to Dzus fasteners.
Just that you ( or the next owner) can if you want to.
With the exception of two holes you’ll need to drill, nothing is taken away from your bird that would prevent you returning it to stock condition.
And if you’re in the business of flying & not fixing, this is for you too. We truly have brought the installation burden down to filing one notch and drilling two holes.
Even if you don’t own a 100 degree aircraft countersink (so the heads of those screws can lie flush), we’re betting you know someone a few hangars down who can lend you one.
So please take a minute to read & follow the instructions included with the product.
That way you’ll never need to learn about the seventeen ways not to install it!
Which kind of CJ Pilot are you?
A. “Thank God Home Depot stays open late”
B “ Your cockpit has been visited by Atilla the Visegrip Avenger”
C” Shiny Things are better”
D “Authenticity Hardliner”
Whichever cap fits, TYC has new Repro CJ Instrument Panel securing screws to pimp your ride’s front and rear pit, whether you’re doing a custom panel with us or just tidying up “the office”.
In the Product page drop down box you can choose Stainless or Black Zinc finish.
That’s right, there AREN’T many CJ goodies on TYC, but we still respect you guys with your funky cranked wings.
That’s what it’s all about, right? Trying to walk a mile in the other guy’s shoes.
That CJ driver in the slot behind you has his Prop exactly as close to your tail skid as your tailskid is away from his Prop. This (flying) life of ours is not a dress rehearsal and a little trust goes a long way.
All Yak lives matter ! So what if Yak guys are never really going to understand Mixture levers that work in the wrong direction
You stay classy CJ Drivers!
In your Yak 52 or CJ, if most of your flights are solo, that instructor’s master gear valve in the rear cockpit probably isn’t getting much activity.
Consider taking a qualified GIB around the pattern from time to time just to give this five-port valve some exercise.
Because if you don’t, once the Gear Selector valve in the Rear Pit starts leaking or just gives out - and subsequently gets opened up for inspection.. you might be surprised to find a fetid little mess like this inside.
And if you & your ‘new to you’ 52 or CJ are just getting to know each other, the design of the Instructor’s and Student’s gear control system are an important piece of Yak lore you’ll want to learn.
Just like that mysterious little push button on the top of the rear control column ( on which, more later), significant thought was given to providing essential landing, go-around and braking control for Instructors charged with the training & safety of DOSAAF students.
When you fly solo, the rear pit’s gear lever should be in the middle detent. In this position, the front pit gear valve has complete control of gear position. There are no squat switches on these planes - the gear does what the lever tells it to, any where, any time.
If you ever get to fly with Gennady Elfimov, (and fail to check rear pit gear lever position prior to your next solo flight), you will join the ‘stiff leg’ club, because Gena lowers the instructor’s gear lever EVERY TIME during the landing phase, as soon as he’s seen the Student lower the gear - and it remains down during the taxi back & shutdown.
This was standard DOSAAF training procedure and applies just as much today.
Take off solo with that rear pit lever in the down position and you can put your front gear lever anywhere you like.
The Gear is staying down.
To put it another way, an important part of any Rear pit passenger brief (for non-pilots) might include “- and leave THAT lever right there completely alone”
This gear lever functionality has created so much angst for some 52 owners that it’s not uncommon to see the rear pit gear lever locked to neutral with an aftermarket plate preventing any movement at all. This can often be spotted alongside rear mags wired to 1 plus 2 (just the sight of which gives some people chills in the worst way).
Locked rear gear levers are a recipe for the photo above. Without a little oily air from time to time, O-rings don’t get moisturized and residual condensation runs amok.
Plus, if you’re flying GIB with a buddy in the front who decides today is the day to get distracted during the landing phase, knowing what’s required from the rear pit won’t help the outcome if you can’t move the lever.
Other Yak lore you may have heard about: having the bad luck to have enough air system pressure to start the motor & begin taxying even though you forgot to open the main air valve.
Everything proceeds swimmingly on your way to the holding point until suddenly the brakes seem ineffective. Only those who practice it, or neurotically verify the Main air valve IS on during taxi, will know precisely where to quickly grab and turn - because just a few quarter turns will fix all braking ills - if you can do it quickly enough.
There IS a situation when you don’t want any air in the braking system.
That button on the instructor’s stick momentarily defeats the brake system air pressure - if, for example, the student has over-applied brakes, got the plane skidding on the runway and directional control has been lost.
Chances are, at this point, front cockpit guy will be white-knuckling that brake lever for all he is worth, at which point the Instructor will most likely be shaking the stick to take control while providing some ‘verbal encouragement’.
In a situation like this, sometimes having no brakes will help. If enough forward speed has been lost such that a go-around is no longer an option, momentarily defeating the brakes and allowing your one-ton Combine harvester to roll freely on its tires, ( or at least pulsing the button and limiting the skid) might be your Instructor’s best bet.
As soon as she releases that button on the top of her control column, normal brake function is restored.
But just like the gear lever, this button, too, is seemingly irresistible to five-year-olds of all ages, so include it in the list of things not to be touched when non-pilot passengers are briefed.
Flights to “knock the rust off” are perhaps more critical to brief thoroughly than flights in the middle of the season, when everyone has been current for weeks.
So in the coming days of May and June 2020, if you’ve agreed to help a buddy get back in the air after being grounded for eight weeks or more, be like Gena (and all conscientious Yak 52 GIB safety pilots) - be sure to back P1 up with use of your rear seat Gear lever. You’re not diminishing anybody’s skill or being disrespectful by doing so, as long as it was briefed beforehand.
It’s like insurance you’ll both be glad you took out.
Discuss the go-around, discuss that you plan to back up the PIC’s landing actions by putting your gear lever down too, also during the taxi, landing & roll out and agree on the mouth music you’ll both use to communicate between your cockpits.
With you now strapped in the rear seat & ready to go flying, select the rear undercarriage lever Down as part of pre-flight checks. When on the ground, the rear selector remains down at all times.
Under normal circumstances, ensure the rear selector is always locked, too. The rear lever will only ever need to be moved from Down to Neutral and back Down at the appropriate stages of the flight.
(The only reason to move the rear selector Up would be in an emergency, perhaps to help the task-saturated man in the front, for example, to get the gear up for a forced landing.)
After you’re airborne, at an agreed safe moment, your rear selector goes to Neutral.
On approach to landing, once the gear has been fully extended by the occupant of the front cockpit (three greens!), the rear selector goes down and remains down until the next take-off or go-around.
Now back to the next solo flight immediately following the dual flight just described.
When preparing the rear cockpit for a solo flight, never move the rear selector to Neutral before making sure the lever in the FRONT is Down and locked!
Dozens of pilots have been caught by this. They quickly land after joining the “stiff leg” club. They’re red-faced and perhaps a little rushed to correct their oversight. “Open that rear canopy quick!....Get to Neutral you little bugger!....”
“OH, CRAP!! Selector in the front is still UP!“
Now THAT’s expensive.
We’ve already put up with enough bad things to remember 2020 for - let’s look out for one another and keep any gear up’s out of the picture!
TYC thanks Gennady Elfimov for overseeing the technical content of this article. If you’d like training from the best Yak 52 Instructor on the Planet, start with a visit to http://skytrace.co.uk
That red ribbon in the image below is the forward limit of 52 control column travel.
In this early design, the customer liked the radio placement for ergonomics, however the right hand knob on the GTR 250 would have got wiped off as you can see below..
Anyone who tells you this stuff can be done with 2D CAD is holding one hand behind their back with their fingers crossed. Why risk costly disappointment?
The blank 52 billet panel comes with two repro knobs and new brackets ( sorry, no new drop pins yet), leaving you free to design and cut your own layout.
If you'd like 3D design help, please give us a call at 619 933-2571. CAD models of all the Chinese and Russian instruments are available as well as most of the popular American avionics.
Why settle for flat sheet metal ?
Billet panels are available for Yak 50,52,55 and CJ
To get started on your new cockpit, go to www.theyakcollection.com and type PANEL in the search box.
Customer referrals available !
The Yak Collection...No Nasty Surprises.
TYC is very proud to have our Cooling Gill repair bushing kit featured in the latest issue of Red Alert Magazine. Since it went to press we’ve upgraded the product a little. Here’s a quick look at what has changed.
The drill template still has a molded fence to ensure correct edge distance, but now three stations with drill bushings are provided, so adjacent damaged holes can now be repaired without repositioning the template.
After removing Gills, lock your template in position over the damaged areas.
Do this by pressing two of the drilled-head M4 Gill Vane Position Screws that you just removed (to release the Gill Vane) through the smaller holes in the template and into aligned holes in the ring beneath.
Using the ID of the drill bushing, you can still scribe an accurate circle around the true center of the damage - in preparation for filing by hand- but now instead, if you wish, you can simply pass a drill through the damaged area, saving a little time.
These hardened drill bushings will keep your 5/16” diameter drill bit centered and on a true perpendicular axis. Remember to remove material with the least drill pressure required because the plastic template will soften if excess heat is generated.
Additionally, you’ll see shallow holes have been molded into the inner curved face of the plastic template.
As you progress from one hole repair to the next, these recesses fit the hex heads of repair bushings already installed .
No change to the kit price and three repair bushings with nuts are still included. Once you’ve installed one, the axles feel so solid you will want to continue!
Note that, although very thin, this additional thickness of the repair bushing’s hexagon head at the base of the gill vane has to be accounted for somewhere. If you need to make repairs that are diametrically opposite, be prepared to leave out washers, or file down the short stubs of tubing that protrude from both ends of the Gill vane.
As you remove the Gills, you will almost certainly find some of the Gill Vane Position Screws that have flats worn on them.
A sample of the stainless ones Craig Payne used to make are shown at the top. Replacements for these Gill Vane Position Screws are now available from TYC but in hardened material.
When it comes to removing wear in the Gills assembly, attending to sloppy Gill bearings is a good place to start.
Keep an eye out for more TYC products to fight vibration and wear in the Gills Assembly during the coming weeks.
Radial Engine Cooling Louvers live in a world of high vibration and varying air loads.
Add resonance - and any looseness in rivets or bushings in this mechanically complex Gills assembly quickly shows up as wear.
Tension springs between the gills are there to mask this, but grab any gill without a spring attached and 1/2” of rotational play is not uncommon. If you don’t check for missing louver springs during the Daily Walk around, you may soon discover gills with irreparable damage.
One weak spot of this CJ and Yak 50 Louver design is at the lower end of the steel axle where it passes through a hole in the aluminum ring. On your plane, if you can grasp any Gill/Louver at its base and create perceptible movement, that hole in the Inner ring isn’t round anymore.
The head of the axles that run down the center of the Gills have been formed from round bar into a square T shape (to stop axle rotation) - and there’s a matching slot in fishplates riveted to the exterior cowl ring. Like spokes on a bicycle wheel, tension in these axles via two 7mm lock nuts nuts at the inner end, draws the outer ring into an even circle.
On the Yak 52, which came later, design of the gills assembly changed in these two areas.
The Yak 52 inner ring has riveted M4 anchor nuts for each of the 28 axles ( no fiddly double locknuts involved) and the top of the axle now has a 100 degree countersunk head, slotted so you can adjust tension easily with a screwdriver, (fishplates riveted to the Yak 52 outer ring have a mating countersink instead of the T slot.)
Let’s say your 50 or CJ has many Louvers that are worn in this area.
For Yak 50 owners, one solution is to buy TYC’s fit-and-forget Factory Refurbished Gills assembly, which will have the newer 52 style components.* The prop hub must be removed, but then it’s a simple task of undoing the old brace supports & re-attaching the entire new assembly.
At $2300 USD however, the convenience and reliability of a zero-timed gills assembly comes at a price that may not be for everyone.
For the more cost-constrained, hands-on CJ or Yak 50 owner looking for a robust improvement to one or two sloppy louvers, here is a solution
This repair kit includes a plastic template that will align a larger hole precisely over the original center of any damaged axle holes in the inner ring.
Use the plastic template to scribe a 5/16” circle that encloses most or all of the damage.
Carefully enlarge the damaged hole with a round file to just inside your scribed line....
...then complete the hole by passing a 5/16” diameter hand reamer through the template.
Remove the template & insert the steel bushing provided with its 7/16” hex facing out.
Tighten the MS21042-4 locknut provided onto threads protruding on the inner side. (Use a 5/16” wrench for this locknut).
This new bushing for the lower end of the gill louver has an internal M4x.7 thread to receive the axle.
The last step is to use a piloted 100 degree countersink on the slotted fishplate riveted to the outer ring.
Don’t forget to reinstall the original washers you found on both ends of the louver, then use a flat blade screwdriver to adjust roundness of the assembly.
Ensure all gill louvers have axial free play and remember to reinstall all tension springs.
The critical bearing surfaces between steel and aluminum has been been increased and now the steel axle bears on a steel bushing.
Individual Yak 52 style axles and additional repair bushings/ extra locknuts are available individually on the website.
*(The Yak 50 does not have cut louvers for blast tubes to the compressor, generator etc, so the Yak 52 Factory Replacement Gills set will need these louvers replaced with the solid style when used for a Yak 50)
In the unfortunate event of a gear up, the Yak 52’s wingtip rib often seems to take the brunt of the damage. If you and your mechanic are facing Yak 52 wingtip repair, TYC Is here to help.
These Port and Starboard Yak 52 wingtip ribs have been hand-formed from over a steel pattern, developed from a scan of a new factory part. They are supplied clear anodized with Dichromate coating for best paint adhesion.
These ribs have the recessed formed hole - but without the four nut plates. Our field research revealed that both the orientation and bolt circle diameter of these nut plates vary from one Yak to the next, so we have left them for you to create! One purpose for that large hole with a rolled edge in the center of the rib is to accept a stout bar to take the weight of the outer portion of the wing during separation from the fuselage. You will notice other aligned holes in adjacent inboard ribs.
After the emotions of the moment have subsided, actual gear-up airframe damage is rarely as bad as it looks.
Kudos to those prepared keep another of our Yaks in the air after the unimaginable happens
When structural engineers talk about “efficient” structures, this may be their way of saying they didn’t leave much unstressed metal in the design.
Case in point: Have you been hearing heavy clunking sounds from the upper ends of your Yak 50 gear lately, during ground handling?
The kind of comforting ‘Clunk’ you’d always want to hear two of in the circuit, doesn’t sound right at all when you’re simply manhandling the plane by its tail on the ground.
TYC has replacement Main Gear Axles and Bronze Bushings.
Get the plane safely on jacks, remove one gear fairing and have somebody carefully apply side force to the wheel while you look for relative movement at the pivot joint.
You might see this....
A well-designed pivot joint distributes loads to the participants, (axle, bushings and housings) so they all grow old gracefully together. When failure finally occurs, the designer knew how to make it non-catastrophic - and like a painful knee, noise is there to alert us something is worn or abnormal.
The steel top of the Yak 50 strut ( the ‘trunnion’) has two outrigger towers through which the head and tail of the bolt pass. The outside of the trunnion head has a flat milled in it to prevent the axle’s hexagon head from turning - Shown in white at lower right in the picture below.
In the outriggers, steel bears on steel. By contrast, the inner supports (attached to the wing) are made of Aluminum with press-fit bronze bushings. These bushings take the landing loads into the wing structure. Here the Steel axle runs on Bronze and because of relative movement during gear retraction & extension, grease is delivered through a drilled passage down the axle from a Zerk fitting in its hex head.
The axle is loaded in shear - so its castellated nut with cotter pin just keeps things lined up - no need for it to be so tight that it’s creating axial tension.
-The first surface to go might be the bearing surface of the steel bolt itself. Or the outer diameter of the bronze bushings that have worn the wing housings slightly oval - or the steel bores going out of round in the trunnion outriggers. A replacement axle/ bushing set
needs to be sized to accommodate any of these wear/failure combinations.
Your mechanic will know how they want to go about fixing it, probably involving an adjustable reamer carefully piloted between the both sides of the joint to ensure axial alignment.
The dimensions of this repair axle and bushings set are all over-sized so that material from any interfacing surface can be judiciously removed. This is challenging work, best undertaken by those with prior experience. In the case of the Yak 50 trunnion, (being quite rare these days), needing to ‘put metal back’ (after too much was removed during the repair), would be very undesirable. Do a skills self-assessment before attempting this, and ask for help upfront if you know you’ll need it.
The only good clunks are airborne clunks, and only when commanded by the gear lever.
Please ( have your mechanic) call us if special dimensions are required.
What could be easier than installing a Skybeacon on your Square Wingtip 52 ?
So we made it harder. You have to drill a hole now !
But then physical installation ( that uAvionix don't talk about) is done!
More info here
John flies out of KSEE whenever he can scrape together a few bucks to fill the tanks