View Full Version : Century NSD36A HSI
S-Works
19th Oct 2006, 08:28
I am just in the process of getting an HSI fitted to my Cessna and have sourced a Century NSD360A.
Anyone have any experiance of these? Pitfalls etc? I plan to interface with my shiny new S-Tech autopilot and the GNS430.
drauk
19th Oct 2006, 13:55
AviationConsumer seem to like it. They do a slaved and non-slaved version apparently and obviously slaved is nicer.
It it is vacuum driven (unlike the Bendix/King equivalent) which means if you lose your vacum source you'll lose your HSI. Or presumably, just the DI bit of it, I suppose the localiser and glidescope will work still.
However, if you're using an STEC autopilot presumably it is rate-based on the TC, which itself is presumably electric, so if your vacuum packs up you can just fly on your AP.
S-Works
19th Oct 2006, 14:28
AviationConsumer seem to like it. They do a slaved and non-slaved version apparently and obviously slaved is nicer.
It it is vacuum driven (unlike the Bendix/King equivalent) which means if you lose your vacum source you'll lose your HSI. Or presumably, just the DI bit of it, I suppose the localiser and glidescope will work still.
However, if you're using an STEC autopilot presumably it is rate-based on the TC, which itself is presumably electric, so if your vacuum packs up you can just fly on your AP.
do you have a link to any reviews?
PCentR
19th Oct 2006, 15:35
If it's used and has been sitting around, you may have to rebuild it soon. They have little rubber belts that take shape, then decay when used, getting rubber bits in the instrument. Not many shops work on them, and a rebuild is very expensive. My 360 lasted 2 mo after purchase of plane flown little for 9 mo prior. Avionics shop said this was typical.
A Sandel does much more if you can make the jump.
Avionyx
19th Oct 2006, 15:38
Bose-X,
A very good unit I would say - know many people who like them a lot. Take your time to understand how it works and I think you will get a lot of benefit from it.
Seen a lot more of them the other side of the pond where they do seem to be popular, probably one of the most popular new, non electronic, installs I'd say.
You've made a good choice, sorry but I don't know of any online reviews - I tend not to trust those, prefer first hand accounts myself.
Avionyx
S-Works
19th Oct 2006, 15:55
If it's used and has been sitting around, you may have to rebuild it soon. They have little rubber belts that take shape, then decay when used, getting rubber bits in the instrument. Not many shops work on them, and a rebuild is very expensive. My 360 lasted 2 mo after purchase of plane flown little for 9 mo prior. Avionics shop said this was typical.
A Sandel does much more if you can make the jump.
I looked at the Sandel, over spec for my needs. If I could slave the KR85 ADF into as well it would be worth my while. The 360 is new so warranty applies and my plane is flown daily so I am not to concerned over that. But a good pointer and thanks. Anything else of note?
Since you are getting a new unit this is almost certainly irrelevant, but there is an obscure variation in these units as to whether a heading valid signal pin enabled is or not. Some sensors need it done, and it caused a lot of head-scratching when diagnosing why a new gadget woudn't work. The STEC roll steer may need it. IAE at Cranfield overhauled mine and are very knowledgable.
rgds
421C
L-Band
19th Oct 2006, 18:56
The NSD 360 HSI needs both vacuum and electrics to operate the card.
Lose the vac the DI stops, lose electrics the DI stops.
Make sure that all the units are connected before putting power on otherwise you will damage the slaving acc unit. The flux detectors had a small blue plug on, make sure yours has a black connector on.
They arrive with a pin in the side for locking the glide slope needle, remember to remove this before fitting as it is a pain removing the HSI agian, i know i have been there!!!
L
S-Works
19th Oct 2006, 19:18
Great, all good advice thankx.
IAE at Cranfield are supplying and doing the fit for me. It seems they know what there are doing with this kit.
I am specifically interested in the human side of it, what it is actually like to use compared to the King HSI that I am used to and in comparison to a standard DI and seperate indicator. Whats it like for precision approach? Does having the GS needle on the left only, make any difference?
L-Band
19th Oct 2006, 21:16
You will find the Glide/slope needle small compared to the KCS 55A system. And the G/S needle is hidden until a valid signal is received.
L
S-Works
19th Oct 2006, 22:00
You will find the Glide/slope needle small compared to the KCS 55A system. And the G/S needle is hidden until a valid signal is received.
L
does this cause any problems when using the diaply to fly the glide? Looking at it it seems clear enough I just want to get some practical feedback.
L-Band
20th Oct 2006, 06:50
No, the G/S is fine to use.
These units were standard fit in all Cessna twins as part of the autopilot system.
Piper used these, but the face colours are slightly different.
Go luck with the install.
L