Adverse yaw on Viscount...

[Macs]

Been flying the 'Count, for a few days now, and am now re-addicted to it . One thing I have noticed is that since there is no "yaw damper" or "coupler" you have to pretty much stick and rudder it (Which is part of the reason I like flying it.) I have noticed though, on turns, there is an almost Cessna 172 need for rudder input to coordinate the turn properly. I was wondering if this was in fact the way the Viscount handled in real life; it does not seem far-off, since it has long wings (glider-like), but was wondering if anybody knew how much rudder input was needed when flying the thing for real. I was also wondering what the 2 and 4 markings on the turn coordinator mean? This is just out of curiosity, as I enjoy the plane as-is. Thanks,

Here's a few assorted ones fro recent flights...









and here is the turn coordinator I was talking about...


regards,
Macs

[DaveB]

Hi Macs

I don't think you'd have used much rudder on an aircraft of this size unless it was during the landing phase or when asked to do a particular turn at slow speed. The markings on the turn and slip are calibrated to enable you to make a 'standard' (2 minute) turn (shown by the 2). The 4 would (I presume) give you a 4 min turn

ATB

DaveB :tab:

[Macs]

Hi Macs

I don't think you'd have used much rudder on an aircraft of this size unless it was during the landing phase or when asked to do a particular turn at slow speed. The markings on the turn and slip are calibrated to enable you to make a 'standard' (2 minute) turn (shown by the 2). The 4 would (I presume) give you a 4 min turn

ATB

DaveB :tab:

Dave,
Ok, thanks, very interesting. I'm still curious about the turn and bank, as it would seem to me logical to have the four minute turn on a shallower bank angle than a steeper one (as the one marked as 2); the markings seem to suggest the you would get a faster rate of turn on a shallower bank; and this I figure since the starting point is from the vertical (vertically aligned gyro I suppose on this instrument). Thanks again for your help,
regards,
Macs

[DaveB]

Hi Macs

You've got me thinking now

Someone.. at some point (I get a feeling it was PeterM) posted a full explanation for the markings on this type of turn and slip and it wasn't recently either :roll: I'll have a look to see what I can find ;-)

ATB

DaveB :tab:

[MALTBY D]

I used to know about this, but it's got a little hazy now.
As Dave said, standard rate turn is a full circle in 2 minutes (3 degrees per second).
But as you say, a 4 minute turn is less movement than a 2 minute turn - so the scale can't be refering to minutes.

Thinking back to what I learned about VC10s, I think the '4' reading for the TURN needle would indicate a standard rate turn.
This instrument has standard rate turn divided into quarters 1 to 4.
So, 4/4 is standard rate (2 min), 2/4 is half rate (4 min), 1/4 quarter rate etc.

I'm prepared to be shot down on this, but that's what I'd expect of it.

DM

[Garry Russell]

So 2 is 4 and 4 is 2.

That's nice and clear then

Garry

[MALTBY D]

Yes that's it exactly.
Just look out the window & aim for where you want to be.

I seem to remember Tonks saying that he never looked at the one on the VC10.

DM

[DaveB]

Hi DM..

Yup.. pennies are dropping now. Thank god I never use the darned thing

ATB

DaveB :tab:

[Macs]

I used to know about this, but it's got a little hazy now.
As Dave said, standard rate turn is a full circle in 2 minutes (3 degrees per second).
But as you say, a 4 minute turn is less movement than a 2 minute turn - so the scale can't be refering to minutes.

Thinking back to what I learned about VC10s, I think the '4' reading for the TURN needle would indicate a standard rate turn.
This instrument has standard rate turn divided into quarters 1 to 4.
So, 4/4 is standard rate (2 min), 2/4 is half rate (4 min), 1/4 quarter rate etc.

I'm prepared to be shot down on this, but that's what I'd expect of it.

DM

Ok David, the quarter turn makes sense . I actually wanted to use this as reference, because in the Viscount, the visibility (in FS) is not that good at certain angles, so I wanted to work out a semi-accurate way to make a 270-ish approach via an outbound leg and turn to final (when circling) using instruments. I figured that if I did a 30-45 second dogleg at a 45, after passing overhead of the field and following that with a standard turn to base and final in one swoop at 130 knots, it would take me about 3/4 to 1 mile on the outbound or "downwind", 2 miles to make the 1 minute turn and another 1.5 miles on final to a total of about 4 or so miles. This starting from a pattern altitude of 1500', would put me at a very comfortable 700-800 fpm descent throughout and a nice alignment coming out of the turn to final. In real life, one would kind of eye-ball it I guess. Many thanks again for your help,
regards,
Macs

[MALTBY D]

Well Macs, having now had a proper look in FS, my recollection does fit with the VC10 model.
But there didn't ever seem to be much needle deflection at all on the Viscount model.
So either it don't work, or what I told you is rubbish.
Fraser!?

DM