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silentsage

Airspeed in the Traffic Pattern

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To practice my takeoffs and landings I've created flight plans that circle an airport in a (big) standard traffic pattern. For example, a typical practice flight takes off from KDFW, flies straight for about ten miles, flies crosswind for several miles, then downwind far enough to enter a cross wind path that allows me to intercept an ILS and make an approach approach to the runway, and then land.  These are really big traffic patterns, but they've been useful to learn how to manually fly the aircraft and practices various instrument approaches. 

Altitude in the pattern is 12,000 feet (on the downwind leg), and I've limited the speed in the crosswind and downwind legs in the FMC to 250 knots.  The autopilot, however, (if used) sets a speed of around 300-313 knots regardless of what is programmed in the FMC. 

I'm curious if I'm making a mistake in setting up the FMC.  Or does the real aircraft behave this way?  

Not a big deal, I'm just curious.  The only reason to use the autopilot is to save time on the crosswind and downwind legs by engaging the AP and them using time compression to get to the approach and then resume manual control. 

Last question - does anyone know what the airlines use for type conversion and periodic flight checks? Could make for some interesting flying. 

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Where are you entering the speed restriction. I'm thinking the best way to do this is one of two ways, either entering the speed in the VNAV page somewhere, I guess in the climb and/or cruise page, or doing a speed intervention in the MCP window. Not sure I understand your last question, but I'm guessing the airlines would be using simulators.

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I used to watch AWACS fly local patterns at Tinker AFB, quite a sight.  Tinker is also a depot for the KC-135s and you see them working the local pattern as well.., I always assumed these were flight checks following depot work.  You wouldn't spend money flying local pattern for pilot proficiency as Kevin mentioned, definitely this would be in a simulator.  Equipment flight checks cannot be simulated.

I do not program the FMC to set the pattern, I simply stick one enroute waypoint for the route, which I seldom fly to, and the ILS approach.  I might use A/P and when I do I am dialing in the speed, heading and altitude on the MCP, it doesn't have to be in the FMC.  I typically stick to a traditional radar pattern where downwind is 5 nm and parallel to the final course and my altitude will usually be about 3000 although in reality you'll see them at 1200.  I find the higher altitude makes it easier to takeoff, clean up and accelerate.  I usually do my local pattern work at KIAH.  Nothing wrong with KDFW either but I'm more familiar with Houston since most of my trips into Dallas are to Dallas Executive (Redbird).

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23 hours ago, silentsage said:

To practice my takeoffs and landings I've created flight plans that circle an airport in a (big) standard traffic pattern. For example, a typical practice flight takes off from KDFW, flies straight for about ten miles, flies crosswind for several miles, then downwind far enough to enter a cross wind path that allows me to intercept an ILS and make an approach approach to the runway, and then land.  These are really big traffic patterns, but they've been useful to learn how to manually fly the aircraft and practices various instrument approaches. 

Altitude in the pattern is 12,000 feet (on the downwind leg), and I've limited the speed in the crosswind and downwind legs in the FMC to 250 knots.  The autopilot, however, (if used) sets a speed of around 300-313 knots regardless of what is programmed in the FMC. 

I'm curious if I'm making a mistake in setting up the FMC.  Or does the real aircraft behave this way?  

Not a big deal, I'm just curious.  The only reason to use the autopilot is to save time on the crosswind and downwind legs by engaging the AP and them using time compression to get to the approach and then resume manual control. 

Last question - does anyone know what the airlines use for type conversion and periodic flight checks? Could make for some interesting flying. 

You may tighten up your circuit considerably, by making an early turn at 400ft AAL climb to 2500ft, maintain an angle of bank to 10deg, that will give you above 4-5nm spacing on base leg. 

 

You may use the AP above 200ft AAL after airborne. Just keep Flap 5 speed on down wind. This will save you considerably amount of time. 

 

Once you have master some hand flying skills, you may begin to do a 1500ft circuit with ~2.5nm base leg distance, even a circuit this “tight” it would still take about 5-6min to finish a touch and go. 

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On 29/10/2017 at 1:32 AM, silentsage said:

Altitude in the pattern is 12,000 feet (on the downwind leg), and I've limited the speed in the crosswind and downwind legs in the FMC to 250 knots.  The autopilot, however, (if used) sets a speed of around 300-313 knots regardless of what is programmed in the FMC. 

Because you've gone above 10,000 feet the FMC has assumed you want to accelerate above 250 knots. If you want to extend your circuit this far and this high, the easiest way round this is to use speed intervention and control IAS directly.

 

On 29/10/2017 at 1:32 AM, silentsage said:

Last question - does anyone know what the airlines use for type conversion and periodic flight checks? Could make for some interesting flying. 

Because sim time is so precious airlines don't spend much time doing pattern work in the simulator. It will usually be combined with other exercises. So the lesson would likely be a normal departure but with a failure inserted (engine fire, hydraulic failure, flap failure, etc) that requires a return to the runway. So the crew deal with the failure and at the same time fly a circuit.

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On 10/29/2017 at 1:32 AM, silentsage said:

Last question - does anyone know what the airlines use for type conversion and periodic flight checks? Could make for some interesting flying. 

Dave, most airlines use zero flight time simulators for type conversions and virtually all periodic flight checks these days because it is far safer and also less expensive.  On the rare occasions where a B744 aircraft is used for base training purposes any visual circuits are conducted in daylight and normally flown at 1,500 aal.  If you want to try this on four engines in still air with say the RR B744 use the following:much shortened circuit procedure as a basic guide.  Use a light T/O weight i.e. <max landing wt, Flap 20 and set the aircraft up as usual with FMS correct speeds and settings etc.loaded, including the same DEP and ARR RWY.

TAKE OFF:  stand up thrust levers (1.10 to 1.20 EPR), all four engs stable, brakes off, set T/O power, keep straight (rudder effective >50kts), rotate at VR to approx 12.5 degs NU (aim for 2-2.5 degs/sec) to achieve V2+10kts in the climb.

CIRCUIT:  Fly straight ahead to 1500ft for 1st circuit.  At 1000ft lower nose to 10degs NU to achieve Flap 10 +10kts with Flap 10 set.  At approx 1300ft lower nose again to 6 degs in order to level off at 1500ft and reduce thrust to approx 1.15EPR.  Apply 25degs bank until on downwind heading +/- 2x drift (use PROG2).  Complete After T/O and Approach checks (remember to set Flap 25 or 30 VREF in the FMS!). ABM RWY threshold start stopwatch and continue on Downwind HDG for 45 secs.  Select Gear down, Flap 20 and complete Landing Check.  Apply 20 - 25 degs bank, maintain height initially allowing the speed to bleed off to Flap 20+10kts and then descend at approx 200ft/min in the turn.  On subsequent takeoffs start the initial turn at 1000ft.

FINAL APPROACH:  Establish no later than 800ft and then select Landing Flap.  ATT should be around 3.5degs NU for a normal 3deg approach (halving the G/S will give you an approx ROD) and adjust EPR to achieve VREF+5 kts. Keep the ROD going all the way to the flare.

LANDING:  Some FS pilots think this is the easy part, so I am not going to spoil things by giving away all of the secrets for achieving a good landing here.  Aim to touch down approx 600m from the threshold by flaring slightly at 30ft and keep the wings level.  If you want to perform a touch and go don't arm the autobrakes or speedbrakes on the approach and don't apply reverse or footbrakes after touchdown.  For a Touch and Go you will be very busy and will need to set Flap 20, adjust the Stab trim, set 1.55EPR and keep the speed above VMCG during the roll. 

One of the quickest ways to learn about the handling performance of the aircraft at light weights without getting too bogged down in the FMS and other systems handling is to fly these visual circuits with and without the Flight Directors.  You can turn the RWY ILS indications off by manually tuning a different ILS frequency into the FMS.. Have fun!

Bertie Goddard   

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