As you can see here this is where I indicate my final approach at 2,500 ft at 180 knots of airspeed but I don’t know what my ideal V/S should be to get a good timing to touch down on the runway can someone tell me the ideal best ways to approach or if I’m doing anything wrong with speed and altitude?
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As a rule of thumb, to maintain 3 deg glideslope (5.2% descent gradient): descent rate in feet per minute = groundspeed in knots x 5.
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You should be at above 3500ft at that mark at probably 200kts and depending on the aircraft the descent rate can wary. A good way is probably trying out the same approach with ILS first for the aircraft you wanna try and replicate the same. Once you pass 2500ft when on ILS then reduce to 160kts then once you cross 1500ft reduce to your approach Speed+10kts when on headwind conditions.
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The ideal V/S on approach is 700-800 fpm. The easiest way to achieve this is tuning the ILS so you can follow the glideslope down. If you don’t want to do this, you will need to find the approach plate so you know the correct altitude and waypoint to begin your final descent to the runway.
Honestly it’s recommended to do ILS approach since Heathrow is an airport that wind shear is quite common along with Frankfurt. Also if you are gonna descent without hand flying will have to keep on adjust the v/s for micro corrections to achieve the accuracy so you can aim for the designated point on touchdown zone. Now regarding approach plate alt for most airport’s usually the beginning of the cone is 4000ft msl and speed expected at 180-200kts IAS.
Or you just Divise your approach speed by 2 to follow the 3 degres angle approach path :
ex = If you initiate an ILS at 180kts IAS (indicated) you V/S should be at -900f/m because 18/2=9
And you can apply the same to your final approach speeds to get a perfect stabilized appraoch
ex = You bout to land an A320 with flaps Full and 140kts IAS, so here you simply do 14/2=7 that gives you the most appropriate descent rate of -700f/m for a stable approach
After catching GS check the PAPI lights of runway if it is showing 4 red then you catch LOC and aircraft will automatically desced when it will be perfect altitude to catch GS.
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Jeppesen approach plates do, but FAA ones only have glideslope.
Oh yes I always rely on the visual red or green lights at the runway marking. This tells me if I’m descending correctly or wrongly.
This is another thing… the light may not be aligned with the glideslope signal. Take this ILS 25L at KLAX for example… this is actually pretty common.
This may or may not be simulated in IF, but if you want to strictly follow procedure, if you are cleared for ILS approach follow the glideslope signal until the minimum or until transition to visual (the V on the chart above). Of course if you are cleared for visual approach, you can follow either one. I believe that this is one of the nuances that @Mustang would like to bring up in his other topic: Preferred Approach Type(s)
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Hi,
In most approach situations—especially precision approaches like ILS, RNAV (LPV), or visual approaches with glide path cues—vertical speed (V/S) is what you get, not what you target.
The glide path is the target, not the V/S. Your job is to stay on that 3° descent path (or whatever is called for to reach your target point), and your V/S is simply the result of your groundspeed along that path (which changes with wind), given the starting altitude AGL.
Only in non-precision approaches (e.g., VOR, NDB, RNAV without vertical guidance) or procedural descents where you’re descending between fixes over a known distance would you calculate and fly a specific V/S to meet altitude constraints.