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Jack_C

VIDEO of managing drag during Approach

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Hi all. We have been noticing quite a few people have problems with slowing down and managing drag. So I made a video which points out 2 things: 1) according to my SOPs an average weighted NG (I am assuming they are referring to the -700 series since the bulk of our fleet is 700), to slow from 250-210 in LEVEL flight with NO use of drag devices, will take 35 seconds and approximately 3 miles. Now take a look at the video. It shows about 48 seconds (remember this is an 800!) and about 3.4 miles. So this is pretty darn accurate! 2) I am doing the ILS approach for runway 24L in Toronto, Canada. You will see the runway centreline on the ND. You will also see it for runway 23 because that is what I programmed for takeoff. You can see about 5 miles from LISDU I select flaps 1 and slow to flap 1 speed. I decide to even descend from 4000-3000 feet. In order to do so I thought I would throw out some more flaps to 5. A couple miles back from the FAF you can see I drop the gear and flaps 15. Then I select the landing flap before 1000 AAE. So as you can see it isn't too hard to set up for a landing. Just be prepared. Don't go zooming into the approach above 200 kts!

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Captains- Since Jack does this for a living, I figured it was worth pinning this post so you can follow along with a pro. If it takes you a few tries- don't worry: You are just learning to overcome years of bad flight modeling in FS. This airplane will really teach you how it is done in the real world- and that's the whole fun of it, right? (Thanks, Jack!)


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Now try the approach with the NGX into Queenstown airport, New Zealand! :( Awesome video, espcially in fullscreen 720p!

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1) according to my SOPs an average weighted NG (I am assuming they are referring to the -700 series since the bulk of our fleet is 700), to slow from 250-210 in LEVEL flight with NO use of drag devices, will take 35 seconds and approximately 3 miles. Now take a look at the video. It shows about 48 seconds (remember this is an 800!) and about 3.4 miles. So this is pretty darn accurate!
Not sure about your operator, but here in Canada, none of the 700's have winglets. I would have chalked it up to the 800's larger mass, and the winglets making pretty much everything their stuck to "slippery". To me those numbers would be extremely accurate given those two variables alone.

Cheers,

Cpt. Thad Wheeler

 

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Not sure about your operator, but here in Canada, none of the 700's have winglets. I would have chalked it up to the 800's larger mass, and the winglets making pretty much everything their stuck to "slippery". To me those numbers would be extremely accurate given those two variables alone.
Funny I work right here in Canada in the same town you are from and we have winglets on every one of our 700's!

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Somebody please school me... But shouldn't an 800 model slow down faster than a smaller 700 model in level flight, considering that biggest difference between the two models is that the 800 has a longer fuselage, thus heavier, thus higher level of induced drag on the same wing at the same airspeed? Jack mentions that he would expect the 800 to take longer to slow than the 700? I would think it would be the opposite? Although the 800 has more mass. Maybe the extra drag and extra mass would cancel each other out? JB

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Very nice Jack !! Just as we do it in Ryanair. NGX is a major breakthrough in Fligh Sim technology.I am enjoying this more than the level D sim. How PMDG can include the Real Boeing manuals and all for under 50 euro !!!! I love this software. Big PMDG fan. Well done you guys !!!!!! im Not Worthy.gif Fred.

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Not sure about your operator, but here in Canada, none of the 700's have winglets. I would have chalked it up to the 800's larger mass, and the winglets making pretty much everything their stuck to "slippery". To me those numbers would be extremely accurate given those two variables alone.
Uh I was gonna say I'm pretty sure Jack's work has winglets on every single one of it's 700's...I'm pretty sure on every one of its -800's...and the only "non-wingleted" A/C is their -600. Perhaps you should give ol WestJunk's website a quick browse there highiron...hehe.

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Somebody please school me... But shouldn't an 800 model slow down faster than a smaller 700 model in level flight, considering that biggest difference between the two models is that the 800 has a longer fuselage, thus heavier, thus higher level of induced drag on the same wing at the same airspeed? Jack mentions that he would expect the 800 to take longer to slow than the 700? I would think it would be the opposite? Although the 800 has more mass. Maybe the extra drag and extra mass would cancel each other out? JB
JB:
...Since Jack does this for a living, I figured it was worth pinning this post so you can follow along with a pro.
Jack is an NG FO. So he knows what he is talking about. The 800 is harder to slow down because it has more mass.

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Jack mentions that he would expect the 800 to take longer to slow than the 700?
I think this may be right and it is all about L/D ratio (lift to drag). More 'chubby' aircraft has it lower. 700 is 'chubbier' than 800. This is my very own down to earth explanation. cool.png

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Figured that would be the case durring descent, but for level flight thought it might be the opposite. Thanks for straightening that out. JB

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Beautiful video.Small commentary coming from few fellow simmers I've come to know: Potential management during descent-approach is more than what shown in the video, it's about planning ahead. Jack here showed a well managed decelreations, but it all starts with planning the approach, determining the exact points at which we're going to lower flaps to landing flaps, 15, 5 and 1 (planning is always from the runway and chronologically backwards). Further more, most preset approaches do not include speed restrictions built in, thus a lot of simmers just count on the FMS that brings them to the FAF at 240 kts. Then they are way too fast to land. During the planning, while cruising and not so close to the T/D, plan the speed reductions as said and if possible - enter to the FMS for better VNAV calculation and actual VNAV speed reductions, built in the descent profile.

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