Direct TWINE - fly over/fly by

[radek.domin]

Good morning to all, could anyone help me to understand how to fly this?

On the fly from KBUR to KLAS, I got cleared direct TWINE and resume VNY1 shortly after transfer to departure controller. I was southeast of Twine at that time so I set DIR TWINE on MCDU (A320) and checked that the flightplan continues with VNY1.

I was hoping that the plane would turn direct to Twine and the turn right to Lagne reasonably before Twine. What happened instead (found it just after ATC told me) was that the plane flew almost west from Twine, probably so it would overfly it and leave it on heading 046 for Lagne.

Any idea on how this should be done correctly? Should I just set heading to twine (based on what I see on the nav display) and then turn manually to Lagne? Is there any way how to force MCDU to fly direct to some point no matter what is behind it?

BTW... Not only I've failed I5 (would probably fail it anyway due to my poor preparation), but I've also heard the TCAS alert for the first time because of this. Those 2 fighters were so close I could admire how well the model is done

[Ryan B]

Looks like a flyby on the chart...

If the turn is too tight you could ask for the next fix too.

[wmburns]

Just wondering. What was the auto pilot bank angle limit at the time? How much bank did you see during the turn? What was your altitude at the time? What was the airspeed (looks like 345 Kts on the screen shot)? Did the airplane make a slow lazy rate of turn?

Could an low bank angle limit or high airspeed have prevented the autopilot from making a tight enough turn to intercept the flight path as you expected?

It sure looks like you were pouring on the coals. Was the 200 Kts speed restriction in the class Bravo maintained? Was the speed restriction of 250 Kts below 10,000' maintained?

[radek.domin]

I was definitely much slower before that turn. The screenshot is taken later on where I was over 10k.

I found out that the problem is caused by bug in Aerosoft Airbus x Extended.
http://forum.aerosoft.com/index.php?/to ... wrong-way/

The bug makes it impossible to fly "direct to" for some waypoints. It simply insist on overflying them and exiting in the exact radial as was originally planned.

I'll simply try it again now and will fly the SID manually to avoid such issues. I just want to get over I5 so I can focus on low-precision approaches in GA planes. (I know there is still I9 to do)

[Keith Smith]

Radek: I flew the I-5 in a /A turboprop. You don't have to fly it with a GPS and FMS.

[radek.domin]

That's right Keith but then there is I-09 which asks for jet/big iron. I was thinking it would be easier to get familiar with only one extra plane.

Airbus X Extended is good model working pretty well even in P3D 2.3. The only problem is the buggy MCDU which makes it impossible to fly more complex SID/STAR with some twists. It works well on full departure/approach, but if you get "fly direct to and then resume" it simply looses its head and becomes very unpredictable.

Anyway, I've passed my I-05 yesterday flying the entire SID manually with no autopilot. Very fulfilling experience though

Thanks for great service Keith. Its so exciting to learn all the differences between ATC in Europe and US.

[wmburns]

Back to some of the original questions posed in this thread. What is the correct response under this scenario? Flying with GPS and autopilot ATC says, "cleared direct TWINE. Resume departure". On the GPS the "direct-to" is selected. As we are monitoring what the airplane is doing, we notice quickly that the GPS is not working as expected. So we ditch the GPS and revert to VOR/A navigation. But how do we accomplish the "direct TWINE" part of the instruction? What does the interaction with ATC look like especially considering that the pilot work load likely just increased a TON?

We know we can get to TWINE by following the VTU046R outbound or LAX323R outbound. However the VTU046R is not technically a "fly able" segment West of TWINE.

The options I can think of are:

1. Manually point the airplane in the general direction of TWINE using the GPS map display. Intercept the VTU046R outbound radial since this is next turn to LANGE anyway.
2. Manually point the airplane in the general direction of TWINE but a few degrees to the right so as to intercept the VTU046R towards LANGE.
3. Tell ATC 'unable direct TWINE" and ask for radar vectors to TWINE with a plan to intercept VTU046R to resume the SID. Under this option, do you just say "unable" or do you offer a longer explanation?

What about if the GPS moving map isn't available at all? Not so easy to manually point the plane in the direction of TWINE now. Which likely takes option 1 and 2 off the table.

Likely at the speed everything is happening, option 1 or 2 wouldn't be possible unless the VOR's were set up ahead of time (we all set up two forms of navigation don't we???).

Thoughts?

Link to SID: http://skyvector.com/files/tpp/1409/pdf ... ANNUYS.PDF

OBTW, congratulations on passing the I5.

[radek.domin]

Keith, I've just noticed the Facebook post about making the I-09 optional. It perfectly solves my problem. Thank you for that