Approach Mode

Hello aviators…
I have a question regarding APPR mode…
Each time when i get some winds on the approach and i tab on APPR to activate it; the aircraft starts to swerve vigorously in order to intercept the localizer; although i chose the type of the approach and all waypoints are aligned with the runway. If there’s a wind which makes you shifting a little bit; the aircraft shouldn’t swerve to intercept the localizer in such an aggressive manner like a right angle interception; it should have taken the crab and continues as it was but unfortunately it always started to swerve. Oftenly i intercept the localizer with a speed of not more than 185 knots but unfortunately the aircraft swerve… Any solution for this problem because it ruins the stability of the approach?

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What trim do you use?
what your speed ?

Hello mate,

Just looking for further clarify. Are you safely established on the glideslope and localiser before activating APPR?

Hello dear…
Actually i activat the APPR mode once I get alogned with the localizer and before reaching the FAF on the chart where I started to set my final approach speed… This occurs with a speed of 180-185 knots depending on the weight…

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180-185 knots seems to be pretty fast when you are on final approach. Try slowing your aircraft down to around 150 or 160 at maximum depending on the weight and see if that helps.

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Trim has nothing to do with this as the pink line wasn’t there… Speed as i mentioned not more than 185 knots

Trim has an effect that’s why it’s there.

Once the green diamond starts to get closer tothe center; i slow down to the final approach speed; if i did slow down before that; I’m pretty sure the aircraft would start bobbing up and down

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Trim has nothing to do with horizontal stability… As i told you since the pink line isn’t showing; your aircraft is properly trimmed

Are you intercepting at a 10-30 (preferably 30) degree angle? Intercepting the localizer straight in does lead to this problem.

I tab on the APPR button once the aircraft is aligned with the runway depending on the approach i’ve chosen

But are you going to the localizer straight in or from an angle?

It depends on the approach… Some approaches are designed so the you have to make a 90 degree turn in order to be aligned; some are straight; so it depends (not sure that I understood your question)… Apologize for that

Sorry, I’m bad at explaining things. When catching the localizer, an intercept of 20-30 degrees provides the smoothest transition to the localizer. I’m actually doing this right now. My aircraft (the one in white) is at a heading of 230 for the intercept to runway 26L at KLAS. This is an intercept. Flying straight in causes the swerving since it has to adjust left, right, left, right, until it is extremely accurate, while with an intercept, it can perfect it the first time.

No worry mate, i got your point… Do you mean that you press APPR mode before even entering the cone? I did a flight to HUEN today from OMDB where the transition from the STAR to the approach is like an inverted L shape

He means that if you come at an angle the APPR can find the exact moment it needs to turn to perfectly be aligned to the runway. On the other hand if you align and hit APPR, you may think you’re perfectly aligned which you’re not causing the autopilot to start suddenly turning left and right to align the aircraft. I think those sudden turns shouldn’t happen, the auto-pilot as a whole needs to be revamped. That’s an issue that has been reported by some players.

I got his point… Let’s suppose that I wasn’t aligned with the runway although I chose the approach type for that runway; why the interception is aggressive? The aircraft tries to intercept in a right angle which force it to make over corrections and as a result unstable approach

That’s what I said. Those sudden turns are a problem with how the auto-pilot was designed. It needs to be fixed in order for those turns to be smooth.

Do i need to activate the APPR mode while I’m turning into final before i get aligned with the runway? Is this the best way to align myself with the runway and stabilize the approach?!

Like @Thunderbolt said, come at an angle preferably 30 degrees activate APPR and let it do it’s job. At the moment, that’s the only way to smoothly align with the runway.