As harsh as it sounds, the girls/guys up front are qualified ATPL/MPL holders with current type ratings to fly the aircraft. We, on the other hand, do not in general possess this vital quality. :)Sorry for the flippant remark. It takes time and planning with the correct forecast information to nail vnav descents without drag required warnings and the like. I know I will need a good few hours more to get on top of this simulation. But hey, that is all the fun of it, isn't it?Andrew

No problem mate, I am not an expert.Told that, as another forumer pointed out, it seems engineers are trying to add forecasts auto-fills within the VNAV, less job for the pilots so they can concentrate on other stuff. At least this is my guess but of course you can tell me if I am wrong and where.

The aircraft is designed to descend at 3 degree slope automatically, which VNAV does. Proper data including weather has to be input for correct FMC calculations, which will not require speedbrake use up to MLGW.Both arrivals mentioned, to Rio and Innsbruck conform to this. In Rio the descent from 12,000 to 2,000 feet is planned along 40NM flightpath, which is fine.

As harsh as it sounds, the girls/guys up front are qualified ATPL/MPL holders with current type ratings to fly the aircraft. We, on the other hand, do not in general possess this vital quality. :)Sorry for the flippant remark. It takes time and planning with the correct forecast information to nail vnav descents without drag required warnings and the like. I know I will need a good few hours more to get on top of this simulation. But hey, that is all the fun of it, isn't it?Andrew

Agree.Also don't forget, before pilots take off, one of them has had an extensive briefing about the weather forecast.Also, the operators themselves have people who are busy with the weather and will inform crews -while in flight- significant changes in weather.I know for a fact that for example at Brussels airport, there are about 100 people working for the meteo service.Bert Van Bulck

Surelly you are right, I am still learning.Told that, if the meteo alias the wind plays a so important role why the winds seem to require me to always add drag instead of sometimes blow in front of me ? I mean 90% of my flights the wind is lateral or diagonal and despite the wind is not on my tail I am pretty much all the times required to add drag 4-5-6-7 times during the descent phase.I am learning so this is just a question of a semi noob

The aircraft is designed to descend at 3 degree slope automatically, which VNAV does. Proper data including weather has to be input for correct FMC calculations, which will not require speedbrake use up to MLGW.Both arrivals mentioned, to Rio and Innsbruck conform to this. In Rio the descent from 12,000 to 2,000 feet is planned along 40NM flightpath, which is fine.

Be that as it may, in real life or in the sim, more often than not you simply won´t see the 737 conform to Rio´s arrival without a lot of use of spoilers. Like I said, so much so that the company had to review it´s sop and make new recommendations for flying into Rio (gear down at 7000', 220k descent etc). I have been in more flights than I care to remember from São Paulo to Rio and can atest to this.

just a small side question: the "drag required" message is just announced on the CDU and so, it is easy to miss. Why doesn't the yellow cdu message light come on as for "reset Mcp alt" ?jos denis

just a small side question: the "drag required" message is just announced on the CDU and so, it is easy to miss. Why doesn't the yellow cdu message light come on as for "reset Mcp alt" ?jos denis

There are 3 types of messages !!1. Alerting messages.2. Entry error messages.3. Advisory messages.(These are in order of importance.)Only Alerting Messages illuminate the amber light. ( most important )All messages illuminate the CDU MSG light.Hope that helps.Fred.

Yes Fred, thank you for the info. But in my case, the "drag required" message doesn't illuminate the CDU MSG light. There's only the text on the CDU baseline. So I wondered if I'm the only one?jos denis

Try inputting winds aloft in rte data pages. It makes a big difference in the use of drag, even with a small tailwind. I was on ua flight to sfo last month and we did a 360 on the golden gate 4 arrival because we were too fast and high.Marc

Yes Fred, thank you for the info. But in my case, the "drag required" message doesn't illuminate the CDU MSG light. There's only the text on the CDU baseline. So I wondered if I'm the only one?jos denis

Drag required is an advisory message, not an alert, so it won't illuminate the light. - Peter

Drag required is an advisory message, not an alert, so it won't illuminate the light.- Peter

I think you need to read my post again !We are talking about 2 different lights here.Fred.

I think you need to read my post again !We are talking about 2 different lights here.Fred.

Ah, my bad - The CDU MSG light should work, was thinking of the reset switch :)

Ok, Peter. Thank you. I was confused because Fred said: "All messages illuminate the CDU MSG light."So, scanning the instruments includes watching for advisory CDU messages on the display.jos denis