Go Around / Missed Approach
Gulfstream G450 Flight Procedures
We practice these in the simulator every six months but hardly ever in real life. I find ritualizing the call outs ensures you execute the missed approach correctly even if it is unexpected. It has gotten easier in the G450 since the GV days of "To L and Back." The following assumes you have enhanced navigation.
With enhanced navigation you need to ensure the FMS is doing what you want when you want. If the FMS is properly sequenced for the approach, the data base missed approach procedure takes over your blue needles. If the runway has multiple approaches of the same type to the same runway, or if your clearance was for alternate procedures, you will need to change your lateral navigation mode soon after pressing TO/GA.
Procedure vs. Technique
[G450 AOM, §2B-08-00, Table 1, extracted]
|Mode||Control or Sensor||Parameter||Value|
|TO/GA||Control switches on throttle knob||Speed Hold or Fixed Pitch Command and Wings Level Roll Command||TO: 8° initial pitch up, then pitch command holds V2.
GA: Initial 8° pitch up, then speed hold on FMS speed target or 12° fixed pitch if AUTO speed targets are not selected or are invalid.
NOTE: The GA mode is enabled only if the BARO Altitude is < 16,500 ft, and RAD ALT is < 2000 ft, or airspeed is < 200 KCAS.
Maximum pitch up command is 17°.
Go Around - 2 Engines Operating (1 Engine Operating differences shown in red)
Why? Left on its own, the flight guidance computer will command a fixed pitch of 12° and will ignore all speed commands when GA and MAN speed is commanded, until FLCH is pressed. Once you've pressed FLCH, the speeds are targeted with a 17° upper pitch limit. Target speeds are VLDG-CLB at F39°, VAPP-CLB at F20°, 180 KCAS at F10°, and 200 KCAS (below 2,500') / 250 KCAS (above 2,500') at F0°. These speeds will be exceeded if the 17° pitch limit is reached.
Targetting 200 KCAS when operating with both engines helps keep the pitch under control early on and gets you ready for flap retraction. (You won't get wild pitch ups right after takeoff shooting for VREF+10 or whatever you had set and the pitch will still be limited.) Targeting your existing speed when operating engine-out gets you away from the ground and with the reduced power should be easily controlled.
There are lots of valid arguments to change the procedures to optimize this or that. But this procedure works and is easy to remember.
Two Engine Procedure
[G450 Aircraft Operating Manual §06-02-80]
- PF: "Go Around Flaps 20"
- PM: Move flap handle to 20 degrees.
- PF or PM: "Positive Rate"
- PF:"Gear up"
- PM: Move gear handle to UP, select ground spoilers to OFF. Set/Confirm missed approach altitude is set in the GP preselect window, select/confirm FMS on the PF's Display Controller Nav menu.
- PM: At 400 feet AAL minimum press MAN speed button on the GP and select 200 knots. Press FLCH on the GP.
- At VREF+20 PF: "Flaps Up"
- PM: Move flap handle UP.
PF: Simultaneously accomplish the following: Press TO/GA Button. Rotate smoothly up into the flight director. Advance thrust levers to G/A thrust - if autothrottles are not already doing so.
PF: Ensure "GA" is annunciated on the PFD, rotate to capture V2+10 by keeping speed between the REF and target triangle.
The GA button only works below 16,500' MSL and below 2,000' AGL or below 200 knots. It results in a wings level pitch up of 8° then attempts to hold the commanded speed but no higher than 17°.
VREF is almost always only 4 knots higher going from 39° to 20° flaps, speed will not be an issue.
The PM's left hand starts at the gear handle, goes aft to the ground spoiler switch, up to the guidance panel altitude select knob, left to the PF's display controller.
This will keep the deck angle under control but if your missed approach has a climb gradient restriction you may need to stay at VREF+10.
Flap retract speed for all go around scenarios is VREF+20.
Single Engine Differences
[G450 Airplane Flight Manual §1-22] Single-engine autopilot coupled go-around is not approved. Autothrottle may not be used during single engine approach.
You will not be using autothrottles during the approach and you will have to disengage the autopilot for the go-around.
[G450 Aircraft Operating Manual §06-02-90]
- PF: Simultaneously accomplish the following: Press TO/GA Button. Rotate smoothly up into the flight director PITCH CUE. Advance operative engine’s thrust lever to the MAX thrust stop while smoothly adding rudder to maintain desired track.
- PF: At 1,500 ft AAL (and clear of obstacles) "Flaps Up, Set VSE, Set MCT"
It will be difficult to comply with the "smoothly" directive. You are going to end up with all the rudder you've got but the rate at which you need it depends on engine acceleration. I try to get the rudder in just behind the engines and concentrate on keeping the wings level with ailerons. If you chase bank angle with rudder things will just get worse.
The single-engine versus two-engine go-around procedure omits the 200 knots selection and in its place uses VSE. The AOM notes that VSE is about VREF+20. It is also available on your display controller.
Gulfstream G450 Aircraft Operating Manual, Revision 35, April 30, 2013
Gulfstream G450 Airplane Flight Manual, Revision 35, April 18, 2013