INS and Gyro Drift.

You should better have GPU though...

In real the pilot would launch INS alignment on GPU power and then perform pre-flight check with ground crew.

So when he come back in the cockpit, by the end of the start up sequence and post start check the INS would be ready.

But for "without GPU" start, the pilot launch INS and most systems after engine start.

It's the same for most aircraft, avoid to drain battery before start up (no APU here).

hmm... in DCS World there's an option while on the ground, to connect the GPU ... may be I should try doing it ?

What is (will be) the process on the PCN for correcting INS drift?

What is (will be) the process on the PCN for correcting INS drift?

Hit a button when you overfly a waypoint or designate it through the HUD (ranging) a bit like CCRP designation.

It's not available yet.

I am back from a 01H20 flight to test gyro drift and I see no drift... Waypoint is perfectly on the landmark I chose. What's wrong ? :huh:

I am back from a 01H20 flight to test gyro drift and I see no drift... Waypoint is perfectly on the landmark I chose. What's wrong ? :huh:

I'll check. :book:

My entire attention was on the arc-second bug, which is squashed. :smartass:

Aaaah great ! :thumbup:

Hit a button when you overfly a waypoint or designate it through the HUD (ranging) a bit like CCRP designation.

 

It's not available yet.

And what button might that be? Or sequence of buttons.

Sent from my SM-G900W8 using Tapatalk

And what button might that be? Or sequence of buttons.

Has not been implemented yet.

 

- this is not exactly true; GPS isn't "smooth" enough to be used as a primary "alone" for all the features an INS provides (provided); the real deal today is a hybrid INS/GPS system, with the INS as primary (still), and GPS as an aid; this has all the advantages of the INS (precision in real time, lots of inertial parameters) without the main disadvantages: 1/ initial position is obtained automatically from a GPS fix (no more typing, slow and error-prone) and 2/ intertial position is updated from GPS fixes all the time without having to manually do that from a known landmark (it's more precise, works everywhere...) => essentially reducing the drift to zero.

 

++

Az'

Airbus flies GPS PRIMARY though, for example. Look at RNAV approaches. So your statement isn't true for all aircrafts either.

You misunderstood my point.

Yes, Airbus can use GPS as a primary navigation mean, to know where they are and where their next waypoint is.

But they also still need INS (ADIRUs in fact) to get some parameters with the required precision/smoothness => Those parameters GPS can't manage, due to its very nature.

Example: flight controls.

++

Az'

What is the proper way to enter desired track for a WP? What I mean is if I want to enter WP## (meaning any from 01 to 20) from hdg 097, how do I enter than in PCN with the parameter selector set to RD/TD? When I try to enter a heading on the first data block (left one) it changes, so not sure what I'm doing wrong.

What is the proper way to enter desired track for a WP? What I mean is if I want to enter WP## (meaning any from 01 to 20) from hdg 097, how do I enter than in PCN with the parameter selector set to RD/TD? When I try to enter a heading on the first data block (left one) it changes, so not sure what I'm doing wrong.

I have not tested RD/TD.

Having said that, RD/TD is a very specialized form of waypoint navigation. It is not used to create a new waypoint. It is used to change how you get to that waypoint.

Waypoint parameters are grouped under BUT (target in French) and they are:

- Lat/Lon

- Altitude

- Runway heading

- Runway glideslope

The last two are needed for displaying the synthetic runway.

If you want to enter a new waypoint all you have to do is input the lat/lon coordinates and the ground altitude for it.

I have not tested RD/TD.

 

Having said that, RD/TD is a very specialized form of waypoint navigation. It is not used to create a new waypoint. It is used to change how you get to that waypoint.

 

Waypoint parameters are grouped under BUT (target in French) and they are:

- Lat/Lon

- Altitude

- Runway heading

- Runway glideslope

 

The last two are needed for displaying the synthetic runway.

 

If you want to enter a new waypoint all you have to do is input the lat/lon coordinates and the ground altitude for it.

Thank for the info. I was not trying to create a new way point, I was flying a barcap mission on a border, and wanted to modify the WP so as I enter and exit the WP I do not cross over, so entering and through a specific heading.

Thank for the info. I was not trying to create a new way point, I was flying a barcap mission on a border, and wanted to modify the WP so as I enter and exit the WP I do not cross over, so entering and through a specific heading.

For those specific problems it is better to use offsets. These are grouped under BAD (French acronym for Additional Target):

- Lat/Lon: You use these to displace the waypoint cross from its origin to a new position.

- Altitude: You use this to change the waypoint altitude.

- Rho/Theta: You use this to set a new waypoint by indicating distance in NM (Rho) and a bearing (Theta).

These allows you to change the position of the waypoint without actually having to change waypoint parameters.

BAD Lat/Lon are not geographical coordinates but distance values:

- Lat displaces the waypoint X kilometers to the North or South of Waypoint position.

- Lon displaces the waypoint Z kilometers to the East or West of Waypoint position.

It is in kilometers because this info is usually relayed by an attached Forward Air Observer in the ground who is using a ground map and those have distances in kilometers.

The BAD altitude value is the difference between the waypoint altitude and the offset. So if you enter +1,000 feet. It will add 1,000 feet to waypoint altitude. If you enter -850 feet, it will subtract 850 feet from waypoint altitude.

Rho and Theta are polar coordinates towards the offset position. Rho is distance in NM and Theta the angle of bearing. These are usually provided by Air controllers like an AWACS and thus use NATO standards.

In other words you can generalize BAD parameters as follows:

- BAD Lat/Lon and altitude are ground offset coordinates used to bomb targets.

- Rho and Theta are air offset coordinates used to intercept something.

Unfortunately BAD navigation is not enabled at this time but I hope to have it ready by Friday.

Again, thank you sir.

yesterday I've spent ~2 hours online in one sortie with a fully aligned INS

landed twice on different airfields

and didn't notice a small yellow N.DEG light on the PCN panel ...

I guess it lit up after first landing - I noticed it only in flight

but I still kept using INS and entered different waypoints ... and what surprised me most - it was still accurate! I mean, of course there was some drift, but nothing crucial - successfully made it to desired point

and I didn't see a warning text on the HUD about INS not working properly... is this how it's supposed to be ? or a bug ?

Did you make sure to ask if the server allows for Gyro drift or not?

It´s a server enforcable feature...you can either turn it off or on.

So when you say online, the server might have simply turned it off?

as I said - gyro drift was present

yesterday I've spent ~2 hours online in one sortie with a fully aligned INS

landed twice on different airfields

and didn't notice a small yellow N.DEG light on the PCN panel ...

I guess it lit up after first landing - I noticed it only in flight

 

but I still kept using INS and entered different waypoints ... and what surprised me most - it was still accurate! I mean, of course there was some drift, but nothing crucial - successfully made it to desired point

and I didn't see a warning text on the HUD about INS not working properly... is this how it's supposed to be ? or a bug ?

Did you made a rearm/refuel after your first landing?

If you did, you were supposed to do a memory alignment (ALCM). It takes 90 seconds. But at this time there are no penalties for not doing it, in the future who knows. :music_whistling:

Did you made a rearm/refuel after your first landing?

 

If you did, you were supposed to do a memory alignment (ALCM). It takes 90 seconds. But at this time there are no penalties for not doing it, in the future who knows. :music_whistling:

yes, I did rearm/refuel after first landing

good to know ! thnx ! :thumbup:

Hi !

A question about ALCM.

Does we have to enter again our actual position in PREP WP00 or not ?

And does we have to shutdown engine or not ?

Thx

Hi !

 

A question about ALCM.

 

Does we have to enter again our actual position in PREP WP00 or not ?

And does we have to shutdown engine or not ?

 

Thx

1. No need to because the aircraft has not moved.

2. I'll check. But you shouldn't need to perform an ALCM if you never shut down your engine. The system is running. It is required only if you shutdown the aircraft.

1. OK, I thought because of previous flight drift we have to give it our corrected position. It's a bit the dark side of the force to me this story of ALCM... ^^

2. Ok.

How to you realign the INS if the drift is over 15 miles? It is just not possible?