ADI Glideslope Flags- VC10 & 1-11

VC10 · Post by **VC10** » 04 Mar 2006, 21:13

Apologies if this has aready been discussed., I couldn't find anything on a search of this forum.

On both the One-Eleven & the VC10 if you have a non-ILS frequency selected e.g. 115.03, the GS flag remains in view. This should clear in these conditions.

Post by **DaveB** » 04 Mar 2006, 22:43

Hi Paul

Goodness.. this is going back a bit!! I can't find the relevant info to hand but.. flags on both the HDI and HSI on the VC10 normally indicate a failure rather than an 'in use' mode. Not having the info to hand (I can find the HDI but not HSI info) I'm not gonna put money on it but GS and LOC will visibly flag on an active freq if that freq is out of range or, in the case of the GS, if you are off the glideslope. HSI flags on the VC10 instrument particularly are quite obtrusive and I can't imagine the pilot being best pleased at chunks of his display being obscured by flags!!

I've just had a quick dig around and can't find what I'm looking for. Will dig out the 1-11 tech manual a bit later and get back to you

[edit] Thanks Tonks. You posted that while I was destroying the toyroom. Works for me

ATB

DaveB :tab:

VC10 · Post by **VC10** » 04 Mar 2006, 23:06

I bow to those with a working knowledge on the 'older' types of a/c, but I was under the impression if you have a VOR freq selected that is above 111.75 the GS flag will disappear from view because there isn't a GS signal for it to look for.

So a VC10 flying the Atlantic will have a GS fail flag in view for the whole trip even though it hasn't failed because their is no signal for it to pick up.

It sounds like a recipe for an accident whereby when the GS has failed there is the potential for the pilot to miss it because the fail flag has been in view for the last 6 hrs so the driver is used to seeing it in view.

Post by **DaveB** » 05 Mar 2006, 00:23

That would certainly appear to be the case Paul. Note that on CMk1's (C1K's in a later life) the HSI is identical to the one seen in civvie aircraft but the HDI was pulled from the word go. No RAF aircraft to my knowledge ever had the civvie HDI fitted.. can't say I blame em either as it works in the opposite field to a normal HDI

C1K's still have that original HSI fitted so Tonk's has plenty of hours looking at flags!

I really don't know how the K2's were fitted but K3 and K4's have the standard military HSI.. HDI similar to that in the ex-BA 1-11's and Tridents

ATB

DaveB :tab:

VC10 · Post by **VC10** » 05 Mar 2006, 09:38

Thanks Dave.

I'll accept the VC10 method of operation but I am not convinced of the 1-11 setup. Those orange flags are just too obtrusive. I'll have to ask a former 1-11 pilot I know.

I know the Concorde flags operate in the method I describe, as do modern a/c

Paul

Post by **DaveB** » 05 Mar 2006, 12:03

OK Paul

The instruments on the 1-11 were set up by DM using data from my Laker Airways (Services) Ltd 1-11 Avionics manual so should be correct. I have the manual in front of me as I type but at this point, don't have time to read the relevant passages. If there is a problem with it, I'm sure it can be sorted

ATB

DaveB :tab:

Post by **DaveB** » 05 Mar 2006, 15:33

Bounce...

Paul..

I've had a quick gander through one of my pubs and you may have something with the flags although I can't be certain. DM is the clever one.. I'm the one with the abused credit card and I know you're au fait with the FD108 (although you never managed to get the info I wanted did you!!)

OK.. one bit here that leads me to thinking you're correct..

VOR/ILS information is displayed on the course indicators and flight director indicators. The VOR/LOC flags are visible if no power is available to the selected navigation unit, or in the even of a signal failure, and the course indicator deviation bar operates to display beam centre relative to the aircraft. The To-From arrows operate on VOR frequencies only, and the GS flags and pointers in both instruments are operative only when a localiser frequency is selected...

The next problem is.. how in god's name can the FD108 be programmed in flightsim to hide the flags when an invalid freq is selected AND hide them when a valid freq is selected but course deviation is correct?? The simple answer is you can't.. at least I couldn't anyway

Hopefully, DM will do a low-flypast on this thread and shed a bit of much needed light

ATB

DaveB :tab:

VC10 · Post by **VC10** » 05 Mar 2006, 16:42

Dave,

I don't know how to do it but I had a similar conversation with the Altitude Concorde team (now sstsim.com) and they corrected the error on an update.

I'll contact the beta team there and see how they did it

Sorry about not coming up with the info, but my contacts let me down:sad:

Paul.

Post by **DaveB** » 05 Mar 2006, 16:44

Rgr that Paul.

I know that DM did something along similar lines in the Trident which worked ok so he will be the one (ultimately) to do a fix

ATB

DaveB :tab:

VC10 · Post by **VC10** » 05 Mar 2006, 18:05

Dave,

Here is the response I received. I hope it is of some use

Paul

The GS flag is in view whenever there is no power source or whether the VHF NAV1 radio is tuned to an ILS frequency and no Glide Slope signal is available. So the code might look something like this: