Difficult to slow her down during descent !

[MarkW 1,491]

I have been using the WX forecast from Activesky and importing to the FMC, I probably should also be updating the winds in the DESCENT FORECAST page but have not done so yet.

[andysim 0]

PFPX will also help show you winds during decent stage also. a tailwind will make it harder to come down in time hehe.  I have so far been unable to import the Activesky text into the PMDG WX file as I get "Invalid Entry" when I click the Wind Data Request button.  (I saved the notepad file under the same name as the route with the .wx prefix but it does not work.

 

So I enter them by hand =)

 

 

EDIT, I just found out I had to type in the name of the file before the request lol.  (In my case ENGMEGCC01)

 

Live and learn.

[kjjj11223344 48]

No problems here. I set gear down at around 0.3 DME from the FAF and am always good on speed. I have found that on final, the 777 is much more difficult to keep on speed than the 737. However, if one is ahead of the airplane, it's definitely doable.

[Lawyer+Pilot 126]

Hi all,

 

Flies great but I have a problem slowing her down after passing T/D.

The 777 seems not to slow down enough and as a result I am at a much higher speed when reaching finals.

 

I know this a slippery plane. I use speed brakes, enter desired speeds into FMS but I just can't get it right.

 

Any others having the same problem?

 

 

Thanks,

Christos

Number 1 rule: Stay waaaaaay ahead of this airplane.

 

Number 2 rule: Don't rely on VNAV to manage your altitude AND your speed. In the terminal environment I almost always intervene with a reduced speed and then just dance on the speedbrakes to keep a descent rate of descent.

 

*The other thing to remember is that the 777 will often put itself above path while descending (keeping it comfortable for passengers while the pilot wonders what the heck is taking so long). If you're busy trying to get back on path while continuing to slow down, you're going to have issues. Just get used to it and start managing your speed earlier in the approach.

[EGLL77W 1,508]

Think ahead, think ahead. I couldn't fly RW or sim without doing so. You need to learn the aeroplanes characteristics and how it will perform in various types of weather/weight/vertical paths (etc). It does take some experience to know what the aircraft will do in fifty odd miles.

 

I've seen a bunch of people capturing the LOC/FAC at a stupidly high speed because they're so determined to keep with the planned LNAV & VNAV path. One word: VECTOR! I hardly fly the initial approaches anymore when doing an ILS - even with RNAV/VOR approaches I'll vector to the IAF. If you're too high/low or too fast/slow give yourself more track miles. But if you don't need to, then great, keep to your LNAV track! The more you do it, then the better you'll be at getting a continues descent also. For argument sake - by doing it I learnt that adding a 15NM range arc around the airport with a standard 3 degree glide path, if I intercept the LOC at 4000ft (AGL) at around 15nm it will have me almost perfect. Then if the glide path is less or more than the standard, adjust the altitude I intercept at. Also, use the other ND not being used in approach mode for an ILS which will show you GS before your PFD does.

 

The speed profile I try to keep when no ATC or speed restrictions are in effect are:

 

Abeam/Downwind - 220knts >Minimum Clean Speed (Flaps Up)

Base - 190/180knts

Final Approach Course - 160knts to 6/4DME (Less than 10DME - if greater then I'll keep 180 until 10)

 

I'll switch it up sometimes too. Say if it's really turbulent, then I'll keep the speed back a little earlier so I'm not fighting with it later on (thinking ahead!)

 

Then the other big thing is putting FLCH/VS and speedbrakes to good use. You'll see at many busy airports across the globe, crew needing speedbrakes to gear extension! Practice with it and learn when to use what and understand in the exact moment WHY you are doing what you're doing. Not doing just because I or someone else suggested it. I hate seeing others in FLCH descending through 5000>3000 on an intercepting heading at 2000fpm or something. It leads to you being under the path longer than you want to be. So in that case, take VS with -400fpm thereabouts, which won't get you any crazy speed increases. Watch the GP too - if it's coming down fast then increase your -FPM. Vice versa if you're descending faster than you should be.

 

Now of course if you're online and have ATC then follow their instructions. Even then though - if you cannot concur and need more time/space, tell them. They're there to help and will do the best they can do.

 

So, practice & think ahead of her at all times! Hope that helped somewhat...

[icemarkom 59]

As someone who's consistently being bitten and frustrated by that, can I humbly add one thing to the phenomenal list of suggestions in the previous two posts:

 

1) This is not NGX. It flies differently, it handles differently and needs more thinking ahead than the NGX. What you do in NGX may not apply to T7. It's entirely different plane.

 

Now, if I could only bring myself to follow that advice.

[kjjj11223344 48]

As someone who's consistently being bitten and frustrated by that, can I humbly add one thing to the phenomenal list of suggestions in the previous two posts:

 

1) This is not NGX. It flies differently, it handles differently and needs more thinking ahead than the NGX. What you do in NGX may not apply to T7. It's entirely different plane.

 

Now, if I could only bring myself to follow that advice.

I completely agree with this.

[Joduv 90]

Found something nice on the web : http://www.gadling.com/2011/07/31/cockpit-chronicles-the-eight-ways-to-slow-a-jet/

[cocoroman 0]

Hey Guys, never heard 4x altitude, but What I have learned is: 3x Altitude  and 5X Ground speed will bring you safely to your Airfield.

Obviously you will have to calculate Airport elevation and deduct from your T\O descent.But as one said before, respect your FMC's calculation, and start early enough your descent. That'll make it... 

[benjamin.mccluskey 0]

What we use for the larger aircraft is a modification of the 3 X rule!

 

From SFC to 15000 feet you take your height x 3 plus a speed increment of 1 mile for every 10 kts above 150 KTS! EG: 5000 Feet @ 300KTS 5x3=15 + 15 (150kts + 150Kts) = 30 Track Miles Required

 

The beauty of this method is it's simplicity! Not enough track miles simply revert to FLCH and full speed brake! Too many track miles go to VS and reduce your vertical speed to get back on profile! To use this method you must make sure that your route ahead of you is something realistic and you have your progress page displayed providing accurate track miles to run!

 

Above 15000 feet simply take your height and multiply it by 4! Simple easy to use and this is what we use in the real world flying the big jets hope it helps!

As far as configuring for approach most airlines have very strict stabilised approach criteria these days requiring one to be on speed and fully configured by 1000 AAL to be a little conservative is to be safe! I like to drop gear at 8 Miles to run and flaps 20 @ 7.5 flaps 25 (landing flap) @ 7.0! The beauty of track miles to run instead of altitude is that you can't confuse yourself when operating to airports that are not at sea level JNB and DEN come to mid immediately as potential traps to a stabilised approach!

[Ironkidz 0]

Here would be my 3 pieces of advice:

 

1: Slow before the T/D to make your descent easier to manage. Remember that this plane is all about energy management and once it starts descending, it is harder and harder to slow down without leveling off and loosing precious distance between you and the airport. So slow before the descent and use spoilers if necessary to hold a speed that allows you to manage the energy easier.

 

2: When you get a head wind during your STAR or Vectors, take immediate advantage of it! Deploy spoilers, level off, cut the throttle, etc to leverage the physics in your favor.

 

3: Don't be afraid to override VNAV. I know it can feel strange to take the plane off of its AP and fly the thing manually or through V/S, but sometimes it is necessary. The FMC will tell you that drag is required, but doesn't do the math for you, so fly the thing sometimes! 

[EpicWin 21]

my experiences are that you dont have to touch anything if you have entered values into computer correctly. you can also put speed to intersections just before aligning with ILS to 205 or so. the plane will slow down to achieve this speed at certain point. During approach, i recommend to cross ILS with 180 kts (but that depends on airport, may be lower or higher) and just when you get to 2500ft above terrain start slowing down to be in landing configuration in 1600. there isnt much time to do this and if you dont want to fly final approach with extended speedbrakes, just lower the landing gear earlier than you do with NGX

[CaptCraig 226]

What I have found is every descent/approach/landing is different and if you're flying offline you are all alone.  You SHOULD be flying as if you're all alone anyway, but whatever.  

 

I just landed in KATL and (my mistake) the plane wanted to start it's descent way way too close to the airport.  This was due to a runway change in the STAR and I had to scramble.  It didn't help either that I had a 70+ tail wind at TOD.  I came in above the glide slope for the first time in this beast.  I fought the urge to press TOGA, but seeing as I was 15nm out of the FAF I decided to continue.  The urge was there though because everything was happening so quickly.  I used speed brake only to manage the descent to capture.  There is no need to put out your gear at 7000ft AGL in my opinion.  I did manage to capture, and land a nice crosswind smoker.  

 

The moral is (and this is just from a PPL pilot who flys C172s) that every landing is different, every approach is different, and it all comes down to how you manage the airplane.  FSX gives us a world to play around in, with airplanes that we probably won't ever get to fly.  Play with them.  In the real world you don't get to play :-) 

[Jlonchambon 1]

I agree with all the comments and suggestions.

but when the plane is SUPPOSED to slow down and has NO reason the keep its airspeed, it does not. The green speed trend vector bar doesn’t even move..

 

then lately,  when it finally decides to slow down  ( way too,late) it slows too slow below Vref on final causing the plane to be unstable and getting the “no auto land” light.

i also set the speed manually in intervene mode in plenty of time and the plane still doesn’t slow.

 

oh well that’s life...!

 

[grayal 0]

Just found this thread after having the same slippery issues. The math here is messing me up though. I keep seeing a formula that essentially says Altitude to loose X3 = Distance To Decend needed. Ok this is what doesnt make sense. For example im at FL300 and need to get to 0 for simplicity's sake. 30000ft X 3 = 90000ft. Im gonna need a LOT more than 90000 ft from my destination to decend. Can someone please explain this to me. I'm clearly missing something.