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Hello, my fellow ‘RA-85123 Fan Club’ members,

Before we open this ‘Tu154 Tech Class’ let me report on what’s going on in and around the Club.

First of first, we expect a few more persons to join our club soon. They will be introduced to you as soon as they appear here. I’ve already had a preliminary talk with some of them.

I’m delighted to inform you that we may expect a couple of Russian pilots with previous Tu-154 experience (and pretty good English) to get ‘on board’.

One of them now flies 737s (pictured here) with S7, a second largest airline in Russia after Aeroflot.

As for our ‘Idol, the RA-85123 Herself’, I called my best friend who still flies the baby, but he wasn’t home, - apparently, he was gone flying it Yes, they keep the plane busy, that’s what I may say so far.

I’ll be updating you with any “News That’s Fit to Print”!

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OK, and now: everybody - into the class!

In our time (I guess, not too much has changed since then ) working with any of the former (Soviet) Aeroflot’s divisions all across the country pilots were routinely scheduled to attend the Tech Class (“ТЕХУЧЁБА” - “Техническая Учёба”) at least once a month, often even twice. That’s the way the system believed the proper level of pilots’ knowledge of aircraft technicalities and flight operation ’subtleties’ should be maintained.

Lets talk about some elements of the Tu-154 control system then.

This is a view of the block of controls governing the position of a horizontal stabilizer, and aileron and rudder trim controls. It looks a little bit awkward, but it’s OK, and does the job it was designed for The unit perched on the dashboard above the central instrument panel.

The main feature of the aircraft pitch trim system is that it doesn’t have either smaller ‘tab’ services on the elevator helping alleviate forces on the control column, nor the constantly moving stabilizer - for the same purposes.

This is because the type of hydraulically powered control system used on the aircraft has no ‘manual reversion’ capability, - which simply means ‘no pressure in the hydraulic lines - no controllability’. Moreover, in such a system there’s no ‘feed-back pressure’ on the pitch control column from aerodynamic forces created on the elevator, etc. I.e., there’s in fact no ‘real feel of control’ for the pilots. As it may seem to be ‘no fun’, or even dangerous to fly such an aeroplane, they installed a set of springs to create an ‘artificial feel’ of back pressure from the aerodynamic forces. So, pilots, as they move control surfaces, actually ‘work-out’  - loading and unloading the steel springs which ‘deceive’ them, - make believe they deal with increasing ‘back pressure as they increase displacement of the control column’. Isn’t that funny?

We’ll talk about this in one of the next classes.

As for horizontal stabilizer, it can however be moved. And it always does, - but only when the controlled input to change a position of trailing edge flaps and leading edge slats has been done with this lever

Here’s an image showing a location of the flap lever. Interesting enough, almost all pilots I few with here in Canada, - if I happen to show them Tu-154 flight deck picture, - always point in amusement at those fans. So, I’m sure, if they get onto the real flight deck, they’ll be able to easy locate the flap lever knowing its position with relation to the fans

By mere moving this lever from ‘Zero’ to the next ‘flap notch’, the system makes a coordinated change in the position of not only the trailing edge flaps, but the leading edge slats, and the horizontal stabilizer as well. And moreover, with respect to stabilizer, there’s three ’scenarios’ for its displacement depending on the position of this governor

To find where this thing is, look at the picture of that ‘awkward’ control block bulking on top of the dashboard. And it is the pilot who sets the governor into the appropriate position (”П = ПЕРЕДНЯЯ (FORWARD)”; “C = СРЕДНЯЯ (MIDDLE)”; “З = ЗАДНЯЯ (AFT)”. He reads the trim sheet prepared by load planners (or, by his fellow, the FO), and determines what zone on the graph the C of G of the loaded aircraft falls in - ‘FORWARD, MIDDLE, or AFT‘, and does the respective setting.

Well, now we are almost done with the subject for today.

The only thing left to explain is what is about that text in Russian with some graphics in the top of this post. Well, it is a fragment from a draft paper outlining essentials of the Tu-154 control system, a sort of ‘boiled down excerpt’ from the flight and system operation manuals I prepared for myself to systematize the information. Mind you, we had lots of ‘memory items’ in the FOM! And I believe, there’s been not too much changes since that time until now

(to be continued.. next time be prepared for a knowledge test