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..
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