I struggle to manage my airspeed properly during descent, and I even received two speed violations in a row today.
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@Miss.Linyutong Tip: Don’t try to reduce speed like 300 to 250, but instead reduce by 10 knots instead for example 300-290-280-270-260-250, this much easier to manage and if you find yourself over speeding use the speed brake.
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If you’re talking about slowing from a low 300 to high 200 knots to a moderate 250 knots by 10,000 feet, you could try reducing speed at an altitude 1-3 minutes before your next waypoint in fpm. For example, if you have a waypoint that VNAV has you descend at -3,000 fpm, you could start your speed reduction at 19,000 or down to 13,000 feet. If you’re unsure of how capable the aircraft is with descent, you could play it safe and try 3 minutes out.
Take a look at this section of the user guide here, hope this helps! Flying Guide | Descent Planning
I would always start slowing down earlier than you’d think, especially if it’s a steeper arrival. You can always level off at 11,000 feet if you’re concerned about over speeding below 10,000.
thanks so much! I’ve been struggling with my descent, so this helps a TON!
In everyday aviation, nothing is the same, and it’s no different in a simulator. To slow down to the required speed during approach, you need to have a good understanding of the aircraft you’re flying. Some models are so aerodynamically sophisticated that spoilers used for air braking are ineffective – the Boeing 737 MAX8 is a prime example. Another important factor is mass – both the amount of cargo, passengers, and remaining fuel, but also the aircraft’s mass itself. Greater mass means greater pulling towards the ground, which translates into constant acceleration. Take the Boeing 777, for example. Spoilers work well due to the very large wing area, but the weight and huge engines, which generate significant thrust at idle, cause the aircraft to brake very slowly and sometimes even accelerate until the flaps are extended to increase air resistance on the wings. If you know your aircraft is very heavy, have a strong tailwind, or are a model that typically brakes poorly, begin decelerating around 15,000 ft. Set the engines to idle and, if necessary, use spoilers. Decelerate to a speed of 245-250 kts. If you know you won’t reach this speed before 10,000 ft, halt your descent and level off briefly by disabling VNAV. After decelerating, you can begin descending again.
When approaching an altitude of 8,000-6,000 ft, begin decelerating to a speed of 210-200 kts (extend the flaps according to the protocol for the specific aircraft – for example, a Boeing 737 MAX 8, extend the flaps to the 5’ position). If the aircraft is decelerating very slowly, use spoilers. At an altitude of about 5,000-4,000 ft, slow down to a speed of about 180 kts (this is the checklist time before final approach). For smaller aircraft, it’s 170-160 kts (Embrayer; A220). Here, during deceleration, extend the flaps further and use the spoilers if necessary (for example, on the B737 MAX8, flaps are set to 15’). Reaching final approach altitude, around 2,500 ft, slow down to final speed (which depends strictly on runway length, weight, and weather). Flap use also depends on speed, sometimes maximum deflection, sometimes not—for example, the B737 MAX 8 typically lands with flaps in a 30’ configuration (40’ is reserved for very very short runways).
I suggest you use proper speeds early in your descent (i.e don’t do 340kts every time). A good descend speed should be around 300 kts more or less depending on aircraft type. If you’d like a conservative approach, use the built-in VNAV for descent profile management and adjust speed as required, probably around 11.500ft should be a good idea to start reducing to 250 kts (earlier if your V/S is high or if going too fast). Use speed brakes as you see fit if you notice that deceleration is not going as expected (high gross weight, tailwind, too close to 10.000ft, etc) and don’t be afraid to stop descent completely (V/S 0) to get back on your target speed to continue descent, as the VNAV is way too conservative IMO. You could always crosscheck if youre on the correct vertical profile multiplying distance to go x 3 (being minded of airport elevation, wind and weight) and adding some extra space for deceleration to approach speed and configuration; though with VNAV you should be good. (Example: at 30 NM (x3) you should be around 9.000 ft)
Good luck!
I usually start reducing speed from 330-ish kts to 250kts around 13500-12500ft. Also, especially for the A330, use the flight spoilers liberally. And of course, if you’re still too fast, you can level off and climb a bit to slow down before resuming descent.
Thanks dear
But the average cruising altitude is more than 30 thousand feet, and the next waypoint has a particularly long span than what he seems to have. What should I do?
If you are overspeeding, dont feel wrong to use the speedbrake!
Why should anyone feel wrong for using speed brakes? That’s what they are made for.
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Which aircraft type are you flying?
Exactly the point
I am asking, because it’s all about energy management. With the mass of the aircraft and its speed and altitude you created an amount of potential energy. Masses want to fall down, wings produce lift, turning the loss of altitude into forward speed and every plane type does that differently.
An A380 is much more difficult to slow down than an A350 or B737, so it needs different planning.
When we know your aircraft type, we could give better advice for proper energy management.
i have the same problem here, but on final approach E
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I use it,but it’s to late