Maintain 170knots to the outer marker

[AirbusCG 52]

I have a question regarding the ATC restriction to maintain a certain (usually very high) speed to the outer marker (or some similar distance to the runway).Often when I'm flying on VATSIM and there's many traffic ATC tells me to maintain (for example) 170kt to the outer marker. But when maintaining such a high speed until I'm almost at the runway I can't slow down ealy enough to configure the aircraft for landing above 1000ft, which is the limit where you should have configured your aircraft for landing.How do you do this in real life?

[japascoe 98]

If ATC asks you to do something that your plane is not capable of or that would cause a safety concern you reply: "Unable, <reason>". So in this case: "Unable, won't be able to slow to approach speed in time". Still I would think you could get from 170 knots to Vapp and full landing config in time from the outer marker, which is usually some distance from the runway. Dropping the gear creates a bucketful of drag which can slow you down pretty quickly.

[Spin737 102]

In real life, you'd select 170 on the speed and then you'd have the next slower Flap setting. So landing at 120,000lbs, you'd select F5. That would be a maneuvering speed of just 158, so you're faster than that, which is good.Approaching the restriction, start configuring. If I think I'll cheat on the fix a little. Maybe start configuring 1 mile before.That said, 170 is pretty slow to be worried about configuring. If you're really having a tough time of it, I'd check to make sure your idle N1 is about 30%.

[scandinavian13 5,192]

I would argue that it's not unreasonable. Pull up LiveATC for DCA when they're in south ops and you'll hear "maintain 170 or greater 'til 5 DME" all over the place when it gets busy (most OMs are about 4-5nm out).I'd get into why it's not unreasonable, but Matt took care of it.

[NoahBryant 26]

I'd have to agree that there really shouldn't be any reason you would be having difficulty slowing from 170kts from OM but just tell the controller you are unable and you'll do 160kts or something. From a controller's standpoint, there's not going to be a huge difference, and surely you won't have difficulty slowing from 160.On VATSIM, it's common for less experienced pilots to slow to like 150 or something as soon as they intercept the localizer and that causes problems for other planes who are behind them who want to get to the airport on time :)Gear, Flaps etc are all you need 99% of the time.

[Paul Deemer 13]

If your configured properly at the right time slowing down from 170 knots to VREF +5 +Half the wind factor should not be hard at all.The key is thinking ahead. By the time I reach the outter marker I am already at Flaps 15 and selecting gear down. As the speed bleeds down from 170 to 160 or less I select Flaps 30. I usually carry a full load so my final approach speed usually averages 152-155 knots. The drag from the Landing Gear and Flaps 30 is plenty enough to get you to the correct speed before you touch down on the runway.If you are not able to do this then your either not configured correctly at the right time or you have a throttle issue and your idle is too high. Idle thrust should show in the low 30s. If it is in the 40 range then that is why your having trouble slowing down.

Edited January 5, 2012 by UAL115

[Guest]

In real life, you'd select 170 on the speed and then you'd have the next slower Flap setting. So landing at 120,000lbs, you'd select F5. That would be a maneuvering speed of just 158, so you're faster than that, which is good.Approaching the restriction, start configuring. If I think I'll cheat on the fix a little. Maybe start configuring 1 mile before.That said, 170 is pretty slow to be worried about configuring. If you're really having a tough time of it, I'd check to make sure your idle N1 is about 30%.

Spin, when you have some spare time, it would be really nice if you could post a video of you landing, I still have to see a pro behaviour and I guess it will be a lesson for everyone here, at least just to have a reference.Thanks in advance

[Spin737 102]

Spin, when you have some spare time, it would be really nice if you could post a video of you landing, I still have to see a pro behaviour and I guess it will be a lesson for everyone here, at least just to have a reference.Thanks in advance

I tried to take a video the other day, but my iPhone can't handle a bright snowy outside and show the cockpit and instruments at the same time. You just get somewhat dark instruments and a blindingly white windscreen. I might have something older. . . I'll take a look. I don't think I'll be setting any examples of "pro-behaviour."

[Guest]

I tried to take a video the other day, but my iPhone can't handle a bright snowy outside and show the cockpit and instruments at the same time. You just get somewhat dark instruments and a blindingly white windscreen. I might have something older. . . I'll take a look. I don't think I'll be setting any examples of "pro-behaviour."

You could start from a NGX video and when you have time and possibility a real one.Thx in advance

[Jeffrey L. Whitaker 0]

Emanuel,Paul in post #5 has offered some sound advice. Approaching the OM at 170-180kts is typical. As I arrive at the OM my usual profile has me at 170-180kts with flaps 1-5 depending on winds. As I approach the OM I lower the gear and select flaps 15. As speed bleeds off I alternately reduce speed to the next minimum maneuvering speed and add flaps. This process continues until I stabalize at Vref+wind correction and planned flap setting. You should be stabilized and fully configured no later than 1,000ft. This process can be complicated if ATC has left you a bit high or the approach profile requires an unusually steep descent- in which case early gear extension and the early addition of flaps is essential.Chapter 5 of the PMDG Flight Crew Training Manual is a great resource, which covers this topic in great depth.JW

Edited January 5, 2012 by Jeffrey L. Whitaker

[jturie 0]

If you are doing an approach in VNAV/LNAV and selecting flaps by the numbers, you are forced to configure for landing way too far out....I've had approaches where I've been forced to lower the gear (or else listen to the horn) a good 10-15 miles out due to the FMC speed setting on the approach. In the real world where ATC has 5 planes strung out on final, there's no way that could be allowed, and VATSIM guys like to follow RW procedures as much as practical.I either modify my FMC speeds or switch over to speed control to keep up 170 until OM....as others have said, getting down to Vref+5 from 170 at 5 DME should not be a problem once you drop the gear and hit flaps 30.

[Paul Deemer 13]

That could be why some are having issues. I always use speed intervention and set ot to 170 knots until the outter marker. At the outter marker with the gear going down and Flaps 15, I set it manually again to VREF + 5 + Half the wind Factor. Works like a Charm. At around 1000 feet I disable the AutoPilot and AutoThrottle and land manually.

Edited January 5, 2012 by UAL115

[scandinavian13 5,192]

From a controller's standpoint, there's not going to be a huge difference, and surely you won't have difficulty slowing from 160.

Agreed, and I'll also reiterate that offering us a compromise is big, especially on VATSIM. On VATSIM, for whatever reason, pilots like to wave the PIC Authority flag and when they get something they don't like, many will just say 'unable', which makes my blood boil (one because I'm volunteering for their enjoyment of realistic ATC, and two because I'd never do that as a real world pilot for the sake of getting what I want). Offering an alternative shows me you're willing to work with me to get everyone in happily.

On VATSIM, it's common for less experienced pilots to slow to like 150 or something as soon as they intercept the localizer and that causes problems for other planes who are behind them who want to get to the airport on time :)

That's one of my favorites, but to be honest, as a controller I like slower more than faster. I love the kids who come screaming in at 250 knots and expect me to vector them properly onto an approach with tight vectors. Recently, I've just been issuing speed restrictions on the downwind if I notice they're screaming in. You're definitely right, though. I'll have a perfect flow going and then one guy at the front of the line hits the LOC and slams on the brakes. Reminds me of the old cartoons where all the pieces start slamming together.Here's a video of a VATSIM Friday Night Ops at DCA:

Early on, you can see altitude separation used to help maintain order when one pilot screwed up royally, causing me to scatter the whole flow. At about 0:45, you can see the abovementioned issue, where the guy slammed on the brakes a little too early (the GS showed a low of 150 that far out).

[ccarter06 3]

Many have stated this: stay ahead of the plane. 170 kias over the marker and slowing to final appr speed is very easy. You just have to get the drag out. ATL appr isn't doing it as much any more, but when it's slow into ATL you used to get 250 kias to the marker. Now it's just 180 kias or greater to the marker. That is RW. As far as the flaps are concerned, once you need to start slowing, all you need to do is get below the max speed for the next flap setting, and when you reach that point throw them out. If you really need to slow fast just be ready over the marker, power to idle (it takes time to spin a new speed into the MCP, click off the autothrottle if you want to save a little time), pull the spoilers out, drop the gear, and start getting the flaps out as able. If you take the autothrottle off keep an eye on the airspeed and remember that engines need time to spool (even from appr idle on the 737). Lead the speed by about 10 kts or so, stow the spoilers and start adjusting the thurst levers to stabilize at your final approach speed.

[scandinavian13 5,192]

No offense, but there's no way anyone's getting 250 to the marker. The marker is too close. 250 on the downwind vector, maybe.