[NOBUG] Maybe a bug...or not

Hi all...

I noticed a strange thing: when I set a target (in ME or in my CR37 using LOLA) the target is never where it should be. It always misaligned, 80 meter for 300. 80 meter for 300°. Always...

No wind and I have 5 on my TERNAV.

:(

Do you have an example to show?

Of course...

As you can see, WP2 is in the center of old airport near Kutaisi.

But...

This is what I see in ANF mode during the attack.

Repeat: no wind, TERNAV value is 5.

Ive kinda wondered about that too - I never seem to have target waypoint excatly on target. Even if my nav is accurate and other waypoints are where they should be.

Lähetetty minun EVA-L09 laitteesta Tapatalkilla

It's a big problem when you cant SEE the target and you have to trust in your instruments (es night or in bad weather situation).

Never had that problems.

Of course, I often do some fast training missions taking off at Batumi and destroy something in the middle of the old airport.

Usualy, I get a drift of 1-3 meters at the first run...

Did you "referenced" while standing on the runway?

(Taxi on the runway to take off. Before take off, stand still and align perfectly with the runway. Push the "reference" button.)

Viggen's navigation system also does not like any wild maneuvers, so did you fly gently before the attack run?

Also, when you are dropping bombs and are in the ANF mode, isn't the circle placed there where you point at when unsafeing?

Did you "referenced" while standing on the runway?

(Taxi on the runway to take off. Before take off, stand still and align perfectly with the runway. Push the "reference" button.) Viggen's navigation system also does not like any wild maneuvers, so did you fly gently before the attack run?

IMHO these two are really important, yes.

I would start look after these, they sound most promising to me.

Did you "referenced" while standing on the runway?

(Taxi on the runway to take off. Before take off, stand still and align perfectly with the runway. Push the "reference" button.)

YES

Viggen's navigation system also does not like any wild maneuvers, so did you fly gently before the attack run?

OF COURSE

Also, when you are dropping bombs and are in the ANF mode, isn't the circle placed there where you point at when unsafeing?

IT'S NOT RELEVANT TO THE PROBLEM...

Maybe you should provide a trackfile or video?

Thanks, but I have a life eh eh

I posted 2 images with the problem's description, it's clear enough.

Now, If you have same problem, probably it's a bug. If you havent, I did something wrong but I cant understand what...

:joystick:

I would like your miz file to test under the same circumstances

But here's what I've done. I created teh simples mission possible, with a cold start at Kobuleti and a waypoint right at the base of the mast, at the exact intersection of the two runways carrying AKAN to ensure that I could engage CCIP.

I started the engines+systems and waited for the flags on the CI and ADI to switch off

Once I had loaded the CK37, I taxied to the runway still in BER.

I switched to Nav once at the runway

I did not "reference update as you don't need to: you are rather recommended to make sure your take-off roll is straight.

Once airborne I flew towards B1 (the only waypoint except Take-off and Landing)

With that I get a small fix error of some 50 m, with the nav system in mode 3! (image)

But this isn't a bug. There's one step missing from all "our" procedures and it comes down to the fact that we only ever runway align (standing still which gives you a larger error) or rolling (like I do and a smaller error.

The way the system works is that the CK37 is preloaded with the center point of the runway and its heading (degrees and tenths).

When you pass from BER to NAV with LS selected, the system goes into "alignment and take-off mode". The HUD switches to show VR (rotation speed) and the INS sets itself to "update".

The purpose of this is to tell the system "I'm here and this is the heading".

If you at that point do a rolling update (as recommended and as I do), the computer will take the average of your heading between 100 and 200 km/h and use that as true heading. It will also take the centerpoint of the runway (as I said earlier) and set that as "here" when you reach 200 km/h. If you do a rolling initialization, that point will be quite near the runway centerpoint.

However, when you do a manual update before you roll, you force the system to do that same update where you are then and there using your current heading and position. This will often be 500 m or so from the actual centerpoint. The manual update is only to be used when maintaining a good straight rollout is impaired such as in high side winds or slippery surfaces!

So what you need to do is to set a proper manual fix before IP to minimize the error.

But 50 m error isn't much for a system like this! There is no reason to be more exact than that.

Hope this clarifies things.

Thanks, but I have a life eh eh

 

I posted 2 images with the problem's description, it's clear enough.

Now, If you have same problem, probably it's a bug. If you havent, I did something wrong but I cant understand what...

 

:joystick:

A trackfile consists of 3 clicks after you have finished your flight, and two clicks to upload it here.

It could help to find out if it is a bug, or your fault. And if second, somebody can help you understand.

Quip said:

- Once I had loaded the CK37, I taxied to the runway still in BER.

I've never do it...maybe can be the problem.

- But this isn't a bug. There's one step missing from all "our" procedures and it comes down to the fact that we only ever runway align (standing still which gives you a larger error) or rolling (like I do and a smaller error.

The way the system works is that the CK37 is preloaded with the center point of the runway and its heading (degrees and tenths).

When you pass from BER to NAV with LS selected, the system goes into "alignment and take-off mode". The HUD switches to show VR (rotation speed) and the INS sets itself to "update".

The purpose of this is to tell the system "I'm here and this is the heading".

I love you man!

:megalol:

viper2097 said:

- A trackfile consists of 3 clicks after you have finished your flight, and two clicks to upload it here.

It could help to find out if it is a bug, or your fault. And if second, somebody can help you understand.

Sure, but a trackfile dosent show the problem...for example you cant see target point or CR37 status.

Anyway, I'll upload a trackfile tomorrow :thumbup:

Quip said:

 

- Once I had loaded the CK37, I taxied to the runway still in BER.

 

I've never do it...maybe can be the problem.

 

[snip]

 

I love you man!

:megalol:

 

You must have done the update within (!) 2 minutes after switching from BER to NAV in LS!

And thanks!

You must have done the update within (!) 2 minutes after switching from BER to NAV in LS!

Wait what? Is this a thing?

EDIT: Yes it is. Totally missed/forgot I read this in the manual.