Flt Plan Altitude not correct on HUD 1.5.7

[Apache600]

Hello all,

I have a few waypoints set up on a simple NAV mission, After departure, 1st waypoint is at 5000, 2nd and 3rd waypoints are at 7000, 4th waypoint is destination. The problem is, when flying the route, the HUD directs me to level off at 570 meters for the whole flight. When going to the kneeboard, and looking at the route, the altitudes are correct at 5k and 7k.

 

- Apache600

[RagnarDa]

Yeah the CK37 doesn't support setting a preplanned height

[amalahama]

So it's a feature, not a bug, isn't it?

[RagnarDa]

Yes as far as I can tell the data cartridge doesn't store that information and the commanded altitude will always be set to 500 automatically when taking off. If anyone has any other information I'd gladly change it. Remember Viggen was always intended to fly as low as possible.

[Airbusdriver]

The system is simulated correct. According to the SFI commanded altitude should be 500 after takeoff. Thereafter you select your own commanded altitude by the use of the reference button on the stick. Press it and current altitude becomes commanded altitude. Enganging autopilot in altitude hold also resets your reference altitude.

System uses barometric or radar altitude depending on your selection of HÖJD SI switch.

If SLAV SI switch is on you will lose the commanded altitude (poletrack) indication below 100m as it declutters for low level navigation and the displayed altitude is in increments of 5m instead of the normal 10m. Once above 100m it reappears as you drop out of low level mode.

When you select LANDING NAV mode it also commands 500m until glidepath intercept unless you intervens and press the reference button to command a higher platform altitude for the approach.

Some weapons will also change commanded altitude when selecting ANF mode to satisfy min or max release altitude criteria.

Edited August 28, 2017 by Airbusdriver

[joey45]

5 and 7 K is a bit high for the Viggen isn't it....

[Airbusdriver]

Also forgot to mention when in low level mode (slav si on and below 100m) the reference button is used to make the compass scale come on and off.

 

So the reference button has 3 functions:

1 On ground: align navsystem heading with runway heading (if not used the systems uses the mean heading during acceleration)

2 In flight: Make current altitude demanded altitude.

3 In low level (decluttered hud) mode: HUD compass scale on/off

 

An important switch that needs hotas selection and that a lot of people could benefit from using.

[Apache600]

Thanks guys. I figured that if the computer was smart enough to know the waypoints, it could have also put the reference line for a predetermined altitude. Good to know that's not the case!

 

Yes, 5-7k is high for an attacking Viggen, but this is for a Navigation mission. All you're doing is relocating from A to B in some lousy weather. And for fuel burn purposes, it's more advantageous for a jet engine to be at higher altitudes.

 

Airbusdriver, thanks for the ref. button info. I knew all the stuff except for the low level one with slav si on. That's pretty nifty :)