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tjeuten

Proper technique for manual landing with autothrottle (ILS)

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Hey,

 

sorry if this question has been asked before, but searched around and couldn't find it... so here I go:

 

Afters a good amount of autolands, I want to practice manual landings with the PMDG 777. I've read that it is common practice (even recommended by Boeing) to leave the autothrottles engaged at all times, even when landing manually.

 

So here I am descending on the G/S with autothrottles engaged, autopilot engaged in app mode. Now at around 1000 ft above ground, I disengage the autopilot, whilst keeping the AT on as per recommendation. But I find myself in the obvious need of making small pitch adjustments to keep the bird on the glidepath. My question is, what is the best technique to do so ? Cause I'm having a hard time keeping the G/S indicator centered.

 

On the NGX, where ATs are disconnected on app, I'd give small power adjustments to keep the G/S centered, but on the T7 when the ATs remain engaged, I guess it must be corrected either by yoke pitch or by trim. But I'm struggling and usually end up higer than the G/S over threshold, meaning some floating and serious runway real-estate is lost during the process.

 

Thanks for any tips.

 

TJ

 

ps: if it's of any use, I'm using the Saitek X52 Pro + Saited pedals.

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I guess practice is what you need. When I began to practice manuel landings, it happend to me almost the same. Either to high or to low, but none was good... But having made almost 100 manual landings with this beast I can say that all you need is practice, practice and practice. Try to keep the plane on the G/S, but don't chase it. You shouldn't worry about making "bigger" inputs either. Don't play to much with the trim during approach. Set a proper trim setting when you take control of the aircraft and give further inputs by pulling/pushing the yoke (in case you are at landing flaps, otherwise you have to trim a little). Try having a descent rate of about 750-850ft/min and try to maintain it. Having a look at the descent rate rather than chasing the flight director makes the approach often easier...

 

My last tip for you is to take control of the aircraft earlier than 1000ft AGL. You have way more time to set up your aircraft properly and get confident with the actual handling. I usually disconnect the autopilot just after gear extraction, let's say at 2000ft AGL which gives me twice as many time as you to nail this beast on the runway ;-)

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Try disconnecting the AP at the beginning of the STAR and flying it manually - by the time you get to GS intercept, you should be well used to the handling.

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Also, the FCTM provides a ton of advice.  It's a lot shorter than the FCOMs and has a wealth of pictures to help illustrate the concepts.

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When I intercept the GS, I disconnect the A/T, find a good trim that will keep the plane level and use the smallest adjustments to increase or decrease my descent rate along with the help of engines.. When you watch videos of planes (Especially 737's) All you hear the entire approach is the trim wheel clicking. When I fly, (In real life) Once I find a good trim, I dont use the yoke to control pitch THAT much. What I do is, if I am too low, increase the throttle...too high, idle it and let the plane lose it's own altitude. If necessary, pitch over a little. This works well with most planes in FS, but really, each plane is different and requires a different amount of controlling for a approach.

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if I am too low, increase the throttle...too high, idle it

 

Read the posts in this topic, more importantly read the title....

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Thanks for the replies and advice, keep em coming :-)

 

In the meantime, one question which is kinda related: are you legally allowed to perform an autoland on a "standard" ILS approach, so one where the approach plate does not mention CATII / CATIII ? FSX allows this as it can't tell the difference, but was wondering if it is allowed in the real world (my guess is no) and if the planes autoland system would even be able to technically handle it.

 

Just want to have it confirmed that no CAT II / III ILS always means manual landing, period...

 

Thanks

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are you legally allowed to perform an autoland on a "standard" ILS approach

 

Yes, as long as ceiling/visibility is above CATI minima

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I lovvve manual landings, don't think I have ever performed an autoland lol, what I do disconnect AP/AT when on finals, visibility allowing, if I can see the runway then I will fly manually,kinda got into the habit now. Just not been in the situation that need a full autoland visibility wise.

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ust not been in the situation that need a full autoland visibility wise.

 

Come to Oslo Gardermoen in winter time  :P

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Come to Oslo Gardermoen in winter time  :P

lol went there in the summer posted shots in wheres your 777 thread. I was lucky because there was and OVC layer but broke through the clouds and theres the runway. In winter landings are more FUN!!! but I will return ;)

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Yes, as long as ceiling/visibility is above CATI minima

And I believe you'd have to let ATC know, so they could protect the ILS critical areas, although in the simulator that wouldn't make a difference, so you wouldn't have that issue there.

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Come to Oslo Gardermoen in winter time  :P

 

...or Jæren in the spring.  Rainy much?  Nah...

 

And I believe you'd have to let ATC know, so they could protect the ILS critical areas, although in the simulator that wouldn't make a difference, so you wouldn't have that issue there.

 

Should...but yeah.

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To the original poster's question--approach with AT on--there's this from a 777 captain I know:

 

"As for your yoke versus trim question, it's a matter of preference.  I believe that all good airplanes are designed not to be flown.  In other words, it should take little effort.  I am a big trim it and leave it guy...in almost any airplane."

 

Hope this helps

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Many of the same principles in flying the B777 apply to smaller aircraft. In this case one of the key points would be to make frequent small adjustments to the aircraft trajectory and thrust.

 

Assuming you are able to fly the aircraft down the localiser manually, let's focus on the arguably trickier art of flying the vertical profile. Practice this by establishing finding an approach where the Glideslope intercept occurs at a decent height (not late and thus lower on the approach). Fly this approach in clear weather.

 

Start out by using disconnecting AP at - say - 1000ft to begin. Keep an eye on your glidepath indicator on the PFD and on the PAPI lights adjacent to the runway. If you see a deviation (i.e. PAPIs not showing 2 red / 2 white or the glidepath 'diamond' moving away from the centre of the scale) then make a small trajectory correction. If the deviation continues, make another correction, and another until you correct the trend. Keep these initial corrections small, because shoving the nose over or hauling the yoke back will result in a much bigger correction than you really need, and you'll end up 'chasing' the diamond.

 

Once you get some proficiency handling the last 1000ft of the approach, start disconnecting as soon as the aircraft is stabilised on the approach under AP. Once you have THIS process down, you can practice intercepting the glideslope manually. This requires a bit more finesse, as you have to find the trajectory down the glideslope yourself, but it is not at all hard if you practice it. Very soon you'll find you have developed a sense for how much correction is needed to correct a given deviation.

 

Autothrust can be left in until you have all of the above sorted out. Personally I rarely disconnect the AT until I am stable on the profile, then I use the light blue thrust position indicators to set my thrust controller to the right position before disconnecting, this avoids the likelihood that you disconnect the AT and your hardware commands a big thrust increase or decrease, which will screw up your trajectory altogether! :)

There really is no 'secret' to good handflying other than practice practice practice. I will freely admit to getting caught out sometimes, especially on an offset approach such as at Kai Tak or into Marseilles, where you're making a turn at the same time as acquiring the right profile.

 

Good luck!

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How are you setting up your speed?  This is what I do.  You  should be as flaps 5 as you near the approach, and set your speed to the "15" tick, once the glideslope comes alive gear down and flaps 15, set the speed to Vref +5.  Fly that speed until 100 feet and I dis-engage A/T and go to idle at 10 feet.

 

This is how the 777 instructor guided me on hand flying while keeping A/T on/

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A common term amongst pilots is "A good landing is made at the top of the glide-slope".

What this means in effect is that you should arrive at that point with the a/c already configured for the ILS descent and at the correct speed.

During the descent reduce your speed in stages (usually linked to flaps/gear extension) so that you cross the threshold at Vat+5 (or more if a crosswind).

For example join the localiser at 180kts, reduce speed to the placarded setting as you engage the glide slope. At about 7DME you should be at around 140kts and at 4DME reduce to Vat+ .

If you have the rwy in sight and it present a clear trapeziod shape keep it steady. If it sinks reduce power. If it rises increase power. Obviously your AT will do this for you so all you need to do is adjust the nose. However, that could potentially put the a/c into an unatural landing configuration. So, it's attention to detail all the way down. If you're having to make large inputs at 500ft then expect a go-around.

 

Make sure your engines don't drop to idle. You need plenty of power in reserve in case you have to abort.

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This is what I've noticed when doing a manual landing with the AT on. If you pitch the nose up the the AT will increase power to keep the speed in the MCP, nose down and it will decrease power.

What I usually do is leave the AT on and trim the plane. I've seen this done on 777 on one of those pilots eye video.

I've never had to disconnect AT and all my landings were good

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Tips for landing the 777 manually..

 

 

Wait for Sp1. ;-)

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You said, on the NGX, you'd disconnect the A/T and on the T7 you won't. Why? Every aircraft manufacturing company "recommends" leaving the A/T on, but especially on windy days, disconnecting it is much easier. (thats what pilots and my common sense told me at least)  Look at Lufthansa for example, they have the company policy that, in manual flight, you HAVE to disconnect the autothrust which makes a lot of sense and is also not as boring as leaving it on in my opinion. Also, just try to as minor yoke/thrust inputs as possible to keep an steady approach. 

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You said, on the NGX, you'd disconnect the A/T and on the T7 you won't. Why? Every aircraft manufacturing company "recommends" leaving the A/T on, but especially on windy days, disconnecting it is much easier. (thats what pilots and my common sense told me at least)  Look at Lufthansa for example, they have the company policy that, in manual flight, you HAVE to disconnect the autothrust which makes a lot of sense and is also not as boring as leaving it on in my opinion. Also, just try to as minor yoke/thrust inputs as possible to keep an steady approach. 

 

 

First thing, Boeing does not have Auto thrust.   Second,  Lufthansa does not have that policy across all fleets.  They operate  pretty much  like every other company.  Please check your facts before spreading misinformation. 

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