I can't confirm the V-speeds

[Aether 37]

Hello,

Everytime I press the Right buttons on the CDU to confirm the V-speeds I get the message "Take off speeds deleted".

I tried this several times but couldn't solved it. Has anyone a clue?

Thanks in advance.

 

Cees van der Linden

FYI when P3D v4 came out I started with a clean install of everything.

[Wild_South 41]

Seems odd. Just ensure that your sequence of events is correct:

1: Program the route, the runway, then activate it.

2: Go to DEP/ARR and select the runway and SID. Again, activate it.

3: Go to Perf and ensure all your weights, flap settings, CoG etc are all inputted.

Good luck

 

[Farlis 2,287]

Also make sure that IRS Alignement is finished.

[Aether 37]

Thanks for replying and the suggestions.

I followed the procedure as described in the PMDG 777-200LR/F tutorial #1.

The airplane is in default startup state so fired up and IRS Alignement is finished.

No luck, I get the same "Takeoff speeds deleted".

 

Regards.

 

[Budbud 227]

Hi,

I read in the FCOM v2:

"If performance data changes:
• FMC replaces existing speeds with FMC calculated speeds in small font
• V speeds are removed from the PFD
• PFD speed tape message NO V SPD displays
• scratchpad message TAKEOFF SPEEDS DELETED displays
Note: After an engine is started, the FMC recalculates the takeoff speeds. Any
combination of gross weight, OAT, or pressure altitude resulting in a
takeoff speed change of two or more knots from the previously calculated
speeds, causes the FMC to recalculate takeoff speeds."

Are you sure you don't have one of the parameter changing constantly (issue with weather engine sending wrong or changing data in the sim for instance..., or refueling maybe)?

When the message is displayed, can you see a difference in takeoff speeds?

[Aether 37]

Hi Romain,

Thanks for replying and the help.

As I wrote I followed the PMDG tutorial no parameter changed. I have just P3D v4 and the default PMDG 777 running.

I also tried it with loading a company route but no luck.

No difference in Takeoff Speeds V1 138, VR 138, V2 142.

As I'm waiting for ASP4 final release no weather engine is running.

Regards,

[Budbud 227]

Probably not helping but have you tried to enter manually the calculated takeoff speeds after setting the ref speeds to off (RSK5)?

I don't now whether the FMC takeoff speeds check is disabled when the ref spds is set to off.

At least it can be a work-around until a solution is found to fix your issue.

[Aether 37]

Hi Romain,

I submitted a ticket at PMDG.

Maybe they come up with a solution.

Thanks for your input.

Regards,

Cees

[downscc 1,327]

This one shouldn't be too hard. Cees, the Tutorial steps for setting the V speeds is on page 48, does your CDU look like the photo on page 49? If you follow every step leading you there, it will work every time.  The most common missing steps are not selecting a departure runway, not setting the performance page with ZFW and as mentioned the IRS not ready.

[Aether 37]

Hi Dan,

It's not the first time I have been flying this airplane. I have flown it in P3D v2 and v3 without any problems.

I thought it was me doing something wrong that's why I have used the tutorial to be shure off the correct procedures.

I've tried it multiple times and in different ways with the same outcome.

Thanks for the suggestion.

Regards

[Aether 37]

Well I did some tests and I found the problem.

I own the Saitek yoke + throttle quadrant and had a button of the quadrant assigned to open the ATC window.

When I pressed that button I heard a click but was not aware where that was coming from.

It turns out that that button was doing two processes, open the ATC window and throttle (decrease quickly) F2. (I don’t know how it did that?)

And if the "throttle decrease quickly" process is in place you cannot confirm the v speeds.

So I configured the Key assignment all over again and that did the trick.

 

So the mystery is solved.

Thanks to everybody who replied trying to help me.

[downscc 1,327]

3 hours ago, celin101 said:

So I configured the Key assignment all over again and that did the trick.

The relationship between V speed set and throttle is interesting.  Glad you posted your finding and you're back to making contrails.

[Budbud 227]

3 hours ago, celin101 said:

And if the "throttle decrease quickly" process is in place you cannot confirm the v speeds.

Thanks for reporting the way your issue was fixed. Very interesting indeed it would have never crossed my mind!

[Aether 37]

2 hours ago, downscc said:

The relationship between V speed set and throttle is interesting.  Glad you posted your finding and you're back to making contrails.

Yes it is interesting. And yes I am.   

 

2 hours ago, Budbud said:

Thanks for reporting the way your issue was fixed. Very interesting indeed it would have never crossed my mind!

You're welcome. I've reported this to PMDG maybe it's a bug?

[joona_ 30]

On 6/15/2017 at 6:51 PM, downscc said:

The relationship between V speed set and throttle is interesting.  Glad you posted your finding and you're back to making contrails.

Actually it is not. If you keep pressing F2 or your throttles give a constant throttle decrease command, it will deploy thrust reverses and that will delete takeoff speeds and all takeoff thrust data.