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kmw510

Unable 270 Kts at XXXX

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I get the "unable 270 kts at XXXX" message quite often and can't see any reason why. I fly standard routes from Flight Aware and use the current SIDS and STARS. Is there anything I might be doing wrong or is this common?

 

 

Kevin Wilson

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I see them regularly. The cause is often that the cost index results in a lower speed during the descent than the STAR requires.

 

For example, the BDEGA1 arrival into SFO requires a speed of 280 knots at, between others, LOZIT. However, the cost index I entered results in for example a planned speed of 270 knots during the descent.


Marc ter Heide

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Is there anything I might be doing wrong or is this common?

 

It's common for STARS that require certain speeds, but your ECON DES SPEED is lower than it (the FMC is monotonic - meaning in the descent, it will only plan to get slower, and not speed up). Just change the DES SPEED to the speed for the crossing restriction...ideally well before T/D so you can just delay the T/D and not carry thrust above idle to maintain the speed after beginning the descent.


Kyle Rodgers

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When I get this messege on FMC I delete the speed on the right with DEL, so the route with altitude and speed is recalculated again. Pay atention not to delete the waypoint on the left, of course.

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When I get this messege on FMC I delete the speed on the right with DEL, so the route with altitude and speed is recalculated again. Pay atention not to delete the waypoint on the left, of course.

 

No. Absolutely no. Doing this would put you at risk of a pilot deviation, which should be avoided at all costs. Granted, the sim doesn't come with an FAA inspector to give you a hard time about missing a speed or altitude, but your procedure is incorrect.

 

Modify the speed in the VNAV DES page.


Kyle Rodgers

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In addition to what Kyle said, at least here in Europe I often see an "at or below" restriction in a SID coded as a hard restriction in the NAV data. Changing the type in the LEGS page (e. g. from 280/... to 280B/...) should help you get rid of the error and also help to meet that specific restriction. Check your charts to see what restriction it should be.

 

Regards

Oliver

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Check your charts to see what restriction it should be.

 

Good point. I've seen similar here, too. As someone who usually takes the "always verify with the chart" angle, I agree with you 100%. That's one thing that bothers me on VATSIM, for sure. Since vatpilots very rarely read charts anymore, the controllers rarely ever assign SIDs in the NY area, as they all require reading the chart, and not just selecting the SID in the FMC. So, instead of getting a SID assigned, as would be realistic, I usually get assigned vectors in my clearance. During my readback, though, I usually drop in "able LGA4," or similar, to let them know I can potentially be trusted. Read those charts!


Kyle Rodgers

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I departed EPGD last night on VATSIM expected a SID but got cleared to FL90 !

 

Have to say, since moving from terrible ATC software is a major difference


Vernon Howells

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Getting assigned a SID, luckily, is the norm here. Likewise, you will need your charts for the approach, for in a lot of places - for instance Frankfurt EDDF and Munich EDDM - you'll get transitions to final approach OR simply a direct to a waypoint on a transition, which means you're cleared to fly the whole transition. Nearly impossible without charts.

 

Regards

Oliver

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Getting assigned a SID, luckily, is the norm here. Likewise, you will need your charts for the approach, for in a lot of places - for instance Frankfurt EDDF and Munich EDDM - you'll get transitions to final approach OR simply a direct to a waypoint on a transition, which means you're cleared to fly the whole transition. Nearly impossible without charts.

 

Right, but a lot of EU SIDs are pilot-nav. Here, we have mostly hybrid and vectored, but some are pilot nav. The issue here is that hybrid and vector cannot be fully programmed into the FMC. So, on VATSIM, you get a pilot who selects it in the FMC and happily assumes the plane is just going to do what it needs to do.

 

Nope.

 

The result is that, over time, ATC stopped assigning them because they realized most pilots were accepting the SID assignment and then just not flying it as published.


Kyle Rodgers

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Good point. I've seen similar here, too. As someone who usually takes the "always verify with the chart" angle, I agree with you 100%. That's one thing that bothers me on VATSIM, for sure. Since vatpilots very rarely read charts anymore, the controllers rarely ever assign SIDs in the NY area, as they all require reading the chart, and not just selecting the SID in the FMC. So, instead of getting a SID assigned, as would be realistic, I usually get assigned vectors in my clearance. During my readback, though, I usually drop in "able LGA4," or similar, to let them know I can potentially be trusted. Read those charts!

 

That's odd -- every time I've been out of JFK I've been assigned a SID and climb (normally the MERIT3/Canarsie climb back to LHR depending on time of day and runway configuration) without having to ask.

 

Certainly over on this side of the pond, if a SID is available it will be assigned.

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In the UK i've been assigned SIDs just over at Poland EPGD i got cleared straight to FL90


Vernon Howells

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for instance Frankfurt EDDF and Munich EDDM - you'll get transitions to final approach
I have a question about transitions at EDDF. I think I read on a chart or a forum that the STARS are only used in case of lost communication and the transitions are essentially like STARS they we think of in the United States. Is that correct or not?

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I have a question about transitions at EDDF. I think I read on a chart or a forum that the STARS are only used in case of lost communication and the transitions are essentially like STARS they we think of in the United States. Is that correct or not?

 

Little bit of a mis-interpretation, I believe.

 

They're filed in the plan as a contingency for lost comms. That way the ATC facility knows what you're going to do if you lose comms. That being said, you do not select it on the DEP/ARR page until the STAR is assigned by the controller.


Kyle Rodgers

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I have a question about transitions at EDDF. I think I read on a chart or a forum that the STARS are only used in case of lost communication and the transitions are essentially like STARS they we think of in the United States. Is that correct or not?

I found this note in the AOI, page 1-40:

If no further CLR received beyond ETARU/REDLI/ROKIM, proceed direct FFM and follow previous

cleared STAR.

Use of transition PROCs only when cleared by ATC.

Also, between 22.00 and 4.00 local time, specific STARs should be used according to the charts (UNOKO, ROLIS, PSA and KERAX 1G or 1R).

Marc ter Heide

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