Still need help with 737 landing

Took off from KTLH. ATC took me up surprisingly high (FL330) to get me to KMCO (Orlando).

 

The problem is still very much getting the speed down to something reasonable on the approach. When you're descending at 1,800 fpm and your speed is still well over 200 KIAS, what kind of an anchor do you throw out to get down to around 150?

 

Despite having the APPR set (and below the glideslope) I apparently blew right through the point where you're supposed to acquire the glideslope. When the cows started getting pretty big I realized I was getting somewhat close to the ground - a long time before reaching the runway!

 

Amazingly, after turning off the AP (including the IAS HOLD) and manually horsing the 737 back up in the air, I made a virtually perfect landing. (That right wing view when the spoilers deploy is fascinating.)

 

On this particular approach it just seemed that ATC didn't bring me down to a reasonable altitude during the approach. When I got that last "....you are now x miles, turn right, blah, blah, blah..." I still had not come down to the 5,000 foot assigned altitude. That's where I feel the 1,800 fpm descent was "hurting" things.

 

I sat the other day with a local friend who "...flies the big iron..." all the time. What a disappointment. Everything is run with mouse and keyboard. He flies through a vatco/vatsim and I think he enjoys that more than actually flying with realisim (or learning how to fly realistically) - he effectively spends most of the time baby-sitting the autopilot. He even takes off with the autopilot, so it didn't take long to discern there wasn't going to be much of a lesson there.

 

Is there someone reading this who lives in central Florida? I'm in Leesburg, but I'd be willing to drive a cople of hours away if I could obtain a couple of really good, authentic, lessons.

 

I mostly fly a DC-3 and a Pilatus PC-12. ILS is a piece of cake in those things. I also flew a LearJet 45 quite a bit and ILS isn't too tough there either.

 

Any and all help gratefully appreciated. Trying to spend some time enjoying the flying instead of devoting so much time to equipment building!

 

Art - N4PJ

Leesburg, FL

ATC can be a little slow in regards to getting you down to a proper altitude. If I feel the need to start my descent sooner than waiting for ATC, I will usually request lower altitudes starting about 150 miles from destination. I never really enjoyed being 10,000 feet higher than the airport when only 8 miles away!

I am a looong way from Florida yet would like to offer two tips.

 

Figure out your Top Of Descent (TOD) by subtracting your desired altitude from your current one.

 

Example: cruising at 35,000ft and need to get to 2000ft to intercept glideslope.

 

35,000-2,000=33,000

 

Divide that by 1000

 

33,000/1000=33

 

Multiply by 3

 

33x3=99

 

Add 10%

 

99x1.1=108.9 or 109

 

Start your descent 109 miles from where you need to be at 2000ft.

 

For your rate of descent, groundspeed x 5

 

500 knots ground speed (not indicated airspeed) x5=2500 ft/min descent rate.

 

If your ground speed changes, adjust your rate of descent.

 

Keep a calculator handy and recalc a couple times during the descent to see if an adjustment is needed.

 

These numbers should get you close, every time.

 

If you need to start your descent before ATC calls you, ask for a lower altitude.

 

peace,

the Bean

Thanks Mr. Zippy. StringBean had a similar idea, but his idea appears to be without ATC messing with you! I never thought about asking for a lower altitude and you described my problem to a "T." They had me at something like 7,000 feet, only 9 miles from the airport!

 

That's when it dawned on me that there has to be a practical way for me to either slow down earlier, descend faster, or both. Of course, descending even faster just helps sometimes to keep the speed up!

 

Art

Thanks Bean. You and Mr. Zippy offered pretty much the same thing. Fortunately, I'm not "afraid" of the math and I knew reasonable ways to calculate what the descent *should* be, but ATC throws curves - a lot!

 

The one piece I see in your calculations is the 2,500 ft/min number. I've been climbing and descending consistently at 1,800 fpm. It never dawned on me to simply get down faster. Once in level flight, it's far easier to get the speed down to a dull roar.

 

I actually have a "descent gauge" in my DC-3. If there's an available window, I might add it to my 737 and keep practicing.

 

Thanks for the tips.

 

Art - N4PJ

Leesburg, FL

My short calculation cheat is as follows.

 

a glideslope has a 5% angle. (that's 3.3 degrees I think.)

 

at a 5% angle, the descent-to-distance traveled relation is:

10 miles forward is 3000 ft down.

 

or, also.

around 30 miles forward is 10.000 ft down.

 

---------

when are you descending along a 5% angle?

-when groundspeed (kt) x 5 equals vertical speed in ft/min

 

at 400 kt GS, and -2000 ft/min V/S

you are descending along a 5% angle.

(And you will need 30NM to descend 10.000 ft.)

 

at 400kts GS, and -1600 VS

you are descending along a 4% angle.

(And then you will need more then 30 NM to descend 10.000 ft)

 

------------------------------------------

calculating that, diagrams, relation vertical speed/horizontal speed in same units, distance-descent relationship in various units, all that took me several days.

These two quite elegant fuormula's were the result.

This is why I fly the F/A-18.

I cruise at 40,000, get to about 50 or 60 mi, go to idle and pop the speed-break, then roll over and pull down to 30 or 40° nose down, roll upright and dive down to 2500', level out, bring in the speed-break, and throttle up to maintain 450 kts. Descend more gently to 1200' and do an overhead recovery.

'27 CAG IN THE BREAK!

Saves a lot of brain cramps... ;)

Pat☺

You can probably do that in the 737, but the pax and cabin staff won't thank you for it.

For some strange reason inverted flight and 40° nose down seems to play havoc with the self-loading cargo's nerves... :pilot:

I wonder how my passenger count would hold up if I inverted my 737 to slow things down! LOL Yes, back years ago, I had some experiments with an F-15 Strike Eagle. I did things with that plane that no sane airliner pilot would ever consider.

 

As you've probably already know, I'm an amateur radio hobbyist. I discovered long ago that there's DXing, contesting, rag-chewing, etc. - a little something for everyone. I've discovered the same thing about flight simulation. There's my friend who baby-sits the autopilot with his mouse and keyboard and there's guys who build 747 cockpits in their garage. A lot of room in between for all of us.

 

In real life, I have a friend who owns two planes - a Mooney Ovation and a Lake Amphibian. We mostly fly VFR. We fly to an airport, either identify the pattern (it it's an uncontrolled facility) or call the tower and get the traffic pattern, approval to land, etc. Sometimes, even on a very short flight, the default ATC vectors us to hell and back!

 

I've been tempted to look at something else - Radar Contact? - to see if it's a lot more realistic than the default ATC.

 

P.S. I can just imagine you coming into my local GA facility (technically it's an international facility now!) at about 400 kts, doing a steep chandelle to bleed off the speed for landing and the locals are "....what the f*^% was that?" LOL This stuff is fun, isn't it?

 

Art - N4PJ

Leesburg, FL

One thing that should help is to descend at a much higher rate, especially above 10000 feet. 2500fpm from FL340 down to 10000 ought to get you down to where you have a bit more time to get set up for approach with speed, flaps and such.

If the passengers don't like an inverted pull to a 40° dive, they have no sense of adventure! Heck with 'em I say :)

But that's the nice thing about the Sim world, you're absolutely right. You can make it as realistic as you like. Although a steep dive to low altitude IS part-n-parcel of a Nasal Radiator's repetoir, when you think about it, as is the overhead recovery. In fact, conditions permitting, the overhead is the preferred method. And the neat thing is, you can do it with any kind of aircraft, adjusting speeds as necessary for different planes of course. Not many C-172's are going to enter at 400kts, after all :)

 

Have you tried doing a Google (or Bing if you prefer) search for a 737 Pilot's Handbook, or something similar? Sadly, no NATOPS for those I'm afraid, but maybe Boeing, United or SOMEone has something similar that will give you some good "How-To's"? Come to think, the Navy has 737's in it's fleet, nowadays, maybe there IS a NATOPS for them you can look over?

Just a thought...

Pat☺

Ultimately it's all much simpler than that. Doing the math will tell you what you need to know, and when you need to do it. Excellent and sound advice:

 

But the default GPS will give you a reasonable approximation of the descent rate required to reach a waypoint with a defined altitude. Just read it!

 

Before setting the approach in the default 737, you can use the GPS to provide you with an approximate rate required from your current speed, position and altitude to the runway. Either direct to or flightplanned. The VSR (Vertical Speed Required) field on the left hand side tells you. Don't enter the approach itself (which you wont know at any distance from the airport) just the destination airport in the first instance - normally part of the flightplan anyway.

 

As this updates in real time you can use this sort-of in reverse - simply read off the VSR and when it reaches your desired rate (1,000 to 1,500 ft / min for the 737) just start you descent.

 

Even better, as this is always a Direct To reading, if you adjust the actual vertical speed to a couple hundred feet a minute more you ensure being at the desired approach altitude well before you enter the approach itself. After passing out of the FL and when close enough to the destination you can tune to the approach and get the runway and approach in use and program that in. As you have already `banked` the extra descent rate you can now begin to reduce the actual rate of descent AND begin slowing the aircraft.

 

In practice this is easier to do than explain...

Absolutely! Gotta thank you and Mr. Zippy, StringBean, il88pp and dnPaul - I landed beautifully today. We won't go into detail about the time the plane floated for three miles and crashed in the woods. LOL

 

I did have some problems later with some of my Saitek equipment. I'm going to blame the equipment. That's my story......

 

I think you're spot on. Getting the plane down to an altitude where you can stabilize the aircraft before the next "step" down - or, if you're lucky, it's already the last step and you're under the GS intercept. I think the main problem was that I was relying on the auto-V/S to get me down from the ozone.

 

Also, I've been used to flying the DC-3 (approaching at well under 100 KIAS) and even the PC-12 - darn near a STOL aircraft. Even when you've slowed down to 140-150 KIAS, things tend to happen a lot faster than in the other aircraft I've been flying.

 

I remember reading years ago that the secret to flying a jet was that you "....had to be in front of the plane..." i.e., you had to be prepared waaaaay ahead of time. In a prop plane at 100 kts it's a lot easier to regroup!

 

Thanks again to all you guys (I think there were five of you) for your help.

 

On a side note, I downloaded the SPAD drivers for my Saitek equip. Can't really see a lot of diff at the moment - need to play with it some more.

 

Art - N4PJ

Leesburg, FL

 

I remember reading years ago that the secret to flying a jet was that you "....had to be in front of the plane..." i.e., you had to be prepared waaaaay ahead of time. In a prop plane at 100 kts it's a lot easier to regroup!

 

Thanks again to all you guys (I think there were five of you) for your help.

 

Art - N4PJ

Leesburg, FL

 

Art your statement about having to stay way ahead of a jet is correct, not once but twice!! Many a high hour recip. pilot, including Thruman Munson, has met disaster on the acceleration/not deceleration side of a jet engine's performance curve.

 

With a recip. aircraft when you need power you pull the lever and the power is almost instantly there, like pushing on the accelerator on most automobiles. With a jet, whether turbo prop or turbojet, you have to allow time for the engine compressor to spool its' RPM up before more power arrives.

 

So if you are going to accurately sim any jet engine aircraft you need to learn to keep the engine spinning well above idle and cancel that power out with other measures, like nose up, flaps, gear, and spoilers. So if you must do a go around, wave-off, etc. late in final you'll have power already there once you clean up all the slow-down devices you deployed. ;)

 

You can't safely just drop the throttle back to idle on final like recip. people are often in the habit of doing!!

Are you using the default 737 or an add-on one? Add-on planes can have their own interesting quirks.

 

Assuming it's the default one, an odd thing I've noticed about the 737 and other default jets in FSX is that if you stick with the default setting of 1,800 fpm when you're descending, the aircraft will actually descend at a much shallower angle! Maybe even as little as 500 fpm! Indeed, I have sometimes been told by ATC to expedite my descent in this kind of situation! That could very well be why you end up too high. Not until you activate the vertical speed hold by clicking on the VS dial (or adjusting it with your mouse wheel) will the aircraft actually descend at the rate you want. Nowadays I descend at 2000 fpm, and this generally works pretty well. (By the way, this also holds true when you're climbing. Unless you set the vertical speed yourself, your aircraft will only climb at 500 fpm or thereabouts, the 1800 fpm "default" notwithstanding.)

 

As for adjusting the speed, I use the autothrottle where possible (but make sure you disengage speed hold before you touch down, otherwise your plane will zoom right off the runway!). Initially I set a speed of 270-280 knots to descend from cruising altitude, then dial it down to 250 as I head below 10,000 feet. As I get to the approach altitude, I decrease the autothrottle setting to 210 knots and add a notch or two of flaps. As the aircraft lines up with the glideslope, I decrease speed to 180 and add another degree or two of flaps. Then as it intercepts the localiser, I lower the landing gear and drop the speed to 150, adding more flaps as the plane slows down. I also arm the spoilers and set the autobrake. At the MDA (minimum descent altitude) and having received landing clearance, I disengage the autopilot and autothrottle and touch down manually. By and large, this results in a well-controlled descent and nice smooth landing.

 

It took me a fair while to get to that point though. I have done more than my fair share of bad approaches and crash landings, and probably made just about every rookie mistake in the book. Even now I can still struggle when the airport I'm flying to doesn't have an ILS beacon (although I'm now learning how to use the GPS to help line me up with a runway).

 

Some aircraft, like the feelThere Embraer 145LR, don't have autothrottles. However, they do at least let you set your climb and descent speed, and I found that I can otherwise manage the speed of that aircraft reasonably well. At any rate, I managed to do a ripping good landing in it the other day. (If the airport had not had ILS though, it might have been a different story.)

 

But for the default FSX jets, autothrottle is your friend when it comes to adjusting the speed, although even with autothrottle, it does take a while for a jet to speed up or slow down. Just be sure to disengage it before you touch down. And don't trust the default vertical speed setting - adjust it manually to get the rate you want. The "default" setting might be 1800 fpm, but it's a lie. You can certainly descend at 1800 fpm if you want, but only if you manually set it first.

Not one to argue (much) but umm...

 

Avoid overcontrolling the

throttles as thrust response is immediate.

This is from A1-F18AC-NFM-000, Section 7.3.2 Approach, Page III-7-27.

 

And the F/A-18C v16.1 demonstrates this perfectly :D

Just ANOTHER reason I love flying it. We also managed to get the drag profiles of the different loadouts right, so the Training has less drag than the A-A, but more than the Clean...It all works out great! Right amount of power, instantly at my fingertips, makes it a real joy to fly.

Lately, I've been working on the Mach Loop in Wales. It is one FUN flight!!

 

Sorry, yes almost all modern jets, including the 737, have a pretty slow engine response. My father, who flew them quite a bit during his career at UAL, said that the speed response of the engines was MUCH better above 80%. Below that, very slow. That's why you feel a commercial jet SEEM to accelerate shortly before touchdown. As Rupert mentioned, you want the faster engine response available for go around. Or even if you are a bit short of the TD point, or the runway entirely...ahem..Not that I"VE ever done that...ahem...

Pat☺

Yes, I think Flying Kiwi was spot on with his comments. And, yes, the 737-800 I've been flying is the stock version. My only payware thus far is the Flight1 Pilatus PC-12. Had one years ago and fell in love with it.

 

I too have discovered the quirkiness of the FPM. Often, the stock ATC hands you over to another center just before clearance is issued for a further climb. That's when the FPM seems to get "stuck." I've gotten in the habit of double-checking right after the beginning of an ascent or descent that I'm actually climbing/descending at the rate I expect, instead of 500 fpm being substituted for 1,800 fpm.

 

Descending well over 2,000 fpm certainly seems to work out better when preparing for the initial fix on approach.

 

Also, at least on the stock 737, they've made the start-up process unnecessarily cumbersome. (In my opinion.) I'm generally a start-em-up from a cold start type of guy, but a little of what they've done is silly. There are a few situations where it seems gauges that should be part of the process are not even involved. I have a DC-3 that's the same way. Typically, one should expect to have to turn on the magnetos, the fuel pumps and the primers before engaging a starter. The DC-3 starts up like a champ without either fuel pumps or primer! On the stock 737, following proper procedures often ends up with a "leftover" message about the fuel valve being open. By sort of "cheating" and clicking something that really doesn't seem to work, the error message goes away. It's been a highly discussed hiccup in the stock 737. At any rate...

 

Thanks to you "new particupants" to the thread with additional advice. I suppose that after another 100 or so flights/landings, it will be as second-natured as it is in my DC-3 or PC-12.

 

One of the things I really like about FSX (and some of its predecessors) was the ability to hand-fly some of that big iron instead of *always* relying on the ILS to get the thing back on the ground.

 

Back in the 90s, there was a guy on this forum who was a pilot for an Indian airline. He flew 747s. When asked if he thought a good flight-simmer could land a big jet liner, he was of the opinion that as long as the autopilot still worked, there was a pretty good chance the simmer could get the plane safely on the ground. If the autopilot was out of whack.....

 

He also noted that his company policy was that one out of every three landings was done with ILS active, but hand-flown - just to keep "in shape."

 

My personal practice regimen is to see if I can safely and successfully land the 737 at my local general aviation airport. One of the runways is 6,300 feet. My theory is that if you can land it there, you can probably land it at any reasonable-sized facility. I just think it makes for good practice - particularly when a crash (or an "extended" landing that trashes US 441) doesn't bring out the NTSB investigators! LOL

 

 

Art - N4PJ

Leesburg, FL

For some reason, you're extended "tag line" reminds me of an old story about an engineer, a carpenter and a programmer. The three of them built a soap box car, turned it loose down the hill and it crashed. The carpenter opined that maybe something on the axles or the body was too stressed. The engineer kept studying his slide rule, double-checking all his calculations. The programmer said, "Hey guys. Let's put it back together, shove it down the hill and see if it happens again!"

 

I have a worse joke involving some economists. Go figure! LOL

Good advice. I too have come to the opinion that the flight must be more or less "stabilized" *before* the APR button is pushed. I made some great landings and felt like I was really getting the hang of it, then......

 

On one flight I blew right through the GS intercept and then went haywire getting the plane back under control - mauling a small forest in the process!

 

I intend to continue my practice/experimenting by concentrating on having the plane already slowed down and pretty much already at the required altitude for the LOC and GS intercept. Certainly seems to work out better.

 

In my "disaster" landing, it was pretty disconcerting to be watching the GS diamond slowly coming down, then discovering that my altitude was ratcheting down the numbers pretty fast - followed rather quickly by PULL UP! PULL UP! LOL

 

Of course, what sometimes complicates matters is the default ATC. You draw up a reasonable flight plan that even helps you get somewhat lined up with the runway, then ATC vectors you all over the landscape. "N44PJ you are now 75 miles away. Turn right...."

 

I finally just started designed flight plans to get me moderately quickly from point A to point B and don't announce my intentions to ATC at all! LOL

 

Assuming there's not some bug in the whole thing I don't know about, it seems it's just a question of practice, practice, practice (and, hopefully, practicing the right things!).

 

Thanks for your help.

 

Art - N4PJ

Good advice. I too have come to the opinion that the flight must be more or less "stabilized" *before* the APR button is pushed. I made some great landings and felt like I was really getting the hang of it, then......

 

 

I intend to continue my practice/experimenting by concentrating on having the plane already slowed down and pretty much already at the required altitude for the LOC and GS intercept. Certainly seems to work out better.

 

In my "disaster" landing, it was pretty disconcerting to be watching the GS diamond slowly coming down, then discovering that my altitude was ratcheting down the numbers pretty fast - followed rather quickly by PULL UP! PULL UP! LOL

 

Of course, what sometimes complicates matters is the default ATC. You draw up a reasonable flight plan that even helps you get somewhat lined up with the runway, then ATC vectors you all over the landscape. "N44PJ you are now 75 miles away. Turn right...."

 

I finally just started designed flight plans to get me moderately quickly from point A to point B and don't announce my intentions to ATC at all! LOL

 

Assuming there's not some bug in the whole thing I don't know about, it seems it's just a question of practice, practice, practice (and, hopefully, practicing the right things!).

 

Thanks for your help.

 

Art - N4PJ

 

+1 on all of that. What I often do during IFR weather is make a IFR flight plan With the altitude at say 5,000'AGL of my destination & follow it at what altitude I choose.

 

Then when I'm already near the destination, leveled out at say that destination's 5,000'AGL I call & ask for IFR coverage. And if asked, which sometimes happens I make sure I click NO on "move to start location."

 

Then when I call the local airport, they're expecting me. From time to time they mess with me a little bit but much less than if I did a whole IFR flight.

 

However if they mess with me a lot, I cancel the IFR and do the ILS approach without permission. ATC isn't thrilled, but I'm on the ground. If they tell me I'm not authorized to land, I just turn the speaker off. :rolleyes:

You, stringbean and Mr. Zippy were all "spot on." I've been making more and more flights with the stock B737-800 and descending at much higher rates than what the "default" is set for - like -2,500 fpm instead of -1,800 fpm. In a number of flights, only once have I gotten the plane going too fast. I've also tried to maintain as much realism as possible by watching speeds (from the checklist) at various altitudes, including

 

The last half dozen flights or so have been absolutely nailed. By descending at much higher rates - using default ATC most of the time - there's plenty of time to get the plane stabilized and the speeds/flaps down to what they need to be to nail the GS/LOC.

 

Made one flight without ATC and had to spend a couple of minutes doing calcs to figure out how far away I needed to begin my descent. When you're up there pretty high, the descent starts a lot further away than one might normally think! I know in real life, I've flown between Orlando and Atlanta quite a few times. It seems that just about the time they reach what would normally be cruising altitude, they start back down. And it's about 450 miles from Orlando to Atlanta!

 

Thanks to everyone for their assistance. Just another few thousand hours and I'll be an expert!

 

Art - N4PJ

Leesburg, FL