Emergency instrumentation for cloud encounters

Thanks for the notes. Don't get me wrong, I think an artificial horizon is a very great thing to have. But, just as a point of conversation, I'd be really be surprised if these things were instant-on in the sense that I was talking about. Surely the guts of the system--the AHRS sensors and processors-- have to be up and running for at least a few tens of seconds before the artificial horizon is needed. And I doubt that those few tens of seconds can take place during a spiral dive. I'd love to be proven wrong-- it would make for a very interesting in-flight video.

Seriously, how long would it take to bring the whole system up from a cold start to accurate functioning during

a) reasonably straight-line flight
b) a spiral dive

I submit that there's some advantage offered to having a self-contained turn rate indicator unit that can be powered up quickly regardless of the glider's flight attitude, as a supplement to whatever AHRS-based artificial horizon may or may not be present.

Sure, it's all a question of how far you want to go. But maybe a vario-incorporated artificial horizon plus a stand-alone instant-on (or rapid-on) turn rate indicator with independent self-contained battery power is a reasonable alternative to a purpose-built artificial horizon instrument, at least for the purpose of strictly emergency use.

Food for thought...

S

My LX 9000 with v9 is up within 2 or 3 seconds if I switch to a page which shows it while in a thermalling turn. I understand Dynons and other solid state horizons do the same. Why would you ever bring it up when in a spiral dive? I have no reason to doubt that it would perform correctly, but it sounds rather unlikely if equipped with an A-H to enter IMC without having switched it on.

I think our wires are a little crossed. That's still not a cold start, right? The AHRS is already on.

Anyway my main point is--

If you are flying with nothing, consider the solid state turn rate indicator that I linked to.

If you are flying with a vario-based AHRS-based artificial horizon, that's wonderful. But you might want to consider supplementing with a self-contained solid-state turn rate indicator in case the system goes belly-up or your battery dies.

Back to square one-- an experienced, highly trained, ex-military pilot blew up his sailplane in cloud in wave. I'm sure he never meant to enter the cloud. Wave cloud is squirrely. Who can argue that he would not have been much better off with some sort of turn rate indicator, than with nothing? I'm sure he had lots of partial-panel practice and experience, or at least simulated experience. If you want to argue that an artificial horizon would be better yet-- great. I agree.

S

On Monday, April 20, 2015 at 6:41:50 PM UTC-5, waremark wrote:
My LX 9000 with v9 is up within 2 or 3 seconds if I switch to a page which shows it while in a thermalling turn. I understand Dynons and other solid state horizons do the same. Why would you ever bring it up when in a spiral dive? I have no reason to doubt that it would perform correctly, but it sounds rather unlikely if equipped with an A-H to enter IMC without having switched it on.

The interial various are really "instant display".

They record the information from the moment you turn the instrument on - which is probably when you turned the panel on. Therefore there is no concept of 'on' when switching to the A/H display. The gyros are used as part of the air model and are constantly calibrated by the external information including (in the Vaulter at least) the GPS.

In addition the one I'm familiar with has a built in magnetometer that calibrates to your installation and gives a rather nice always available compass.

Mel

On Tuesday, 21 April 2015 08:29:19 UTC+1, 7C wrote:
The interial various are really "instant display".

They record the information from the moment you turn the instrument on - which is probably when you turned the panel on. Therefore there is no concept of 'on' when switching to the A/H display. The gyros are used as part of the air model and are constantly calibrated by the external information including (in the Vaulter at least) the GPS.

In addition the one I'm familiar with has a built in magnetometer that calibrates to your installation and gives a rather nice always available compass.

Mel


Are the LX devices really running all the time? When you bring up a page showing the A-H it is not actually instant on - it takes a couple of seconds before it indicates that it is live. Presumably the sensors are alive, but there is something else which has to be on before you see the A-H display.

So many solid state A-H's have become available over a short period of time.. According to reports they all seem to work very well. Does anyone know whether the technology (both hardware and software) is common to the different manufacturers, or has each manufacturer developed their own approach? Within the LX Nav range, does anyone know whether the S80/S8 have the same sensors and software as the V9?

Are the LX devices really running all the time? When you bring up a page showing the A-H it is not actually instant on - it takes a couple of seconds before it indicates that it is live. Presumably the sensors are alive, but there is something else which has to be on before you see the A-H display..


I don't know about the LX but that Vaulter is definitely instant display.

Mel

I submit that you might be surprised at what happens if you power up the system in a steep turn. Maybe I'm wrong...

On Tuesday, April 21, 2015 at 2:29:19 AM UTC-5, 7C wrote:
The interial various are really "instant display".

They record the information from the moment you turn the instrument on - which is probably when you turned the panel on. Therefore there is no concept of 'on' when switching to the A/H display. The gyros are used as part of the air model and are constantly calibrated by the external information including (in the Vaulter at least) the GPS.

In addition the one I'm familiar with has a built in magnetometer that calibrates to your installation and gives a rather nice always available compass.

Mel