Contract Airline Services

"We are the protagonists of our stories called life, and there is no limit to how high we can fly."

PHD. MBA. MHS. Type rated on A350, A330, B777, B747-400, B747-200, B757, B767, B737, B727. International Airline Pilot / Author / Speaker. Dedicated to giving the gift of wings to anyone following their dreams. Supporting Aviation Safety through training, writing, and inspiration. Fighting for Aviation Safety and Airline Employee Advocacy. Safety Culture and SMS change agent.

Tuesday, January 3, 2012

A330 Flap Logic

Last week I received a GREAT from Daniel concerning A330 Flap logic.

"Regarding normal flap operation: I never understood how the flaps 1 position worked on an airbus. I see the flap lever only has a "1" position, but the indicator sometimes says 1 or 1+F. So when would it have flaps in addition to slats? Is it an FMS input or system logic?”

This is a great question!

This is how the system works:

Anytime the flap lever is moved to position 1, the slats move.

The question is… when will the flaps come out?

In this photo, the flaps and slats are out… thus the 1+F. Meaning, flaps 1 has been selected, and on the left we see that slats "S" are in position 1, and on the right flaps "F" are in position 1.

If only slats were out, then we would only see 1.

In addition to the slats, the flaps will move to 1 when…

  • Anytime on the ground.
If we’re planning a departure, we want our flaps out, not just the slats. Airbus logic knows this and the flaps will extend too.
  • Anytime we’re retracting from flaps "greater than" 1, the flaps will stay at 1 until we move them to "O" position.

Sequentially this makes sense when retracting. We wouldn’t want them to go from flaps 2 to up, losing our lift, until we're ready

When won't we get flaps 1 when we select the 1 position?

  • When airborne and we go from a clean wing to flaps 1 selection we only get the slats. Flaps will not come out until we select flaps 2 position.

When flying this plane everyone knows that Flaps 1 on arrival doesn’t really do a whole lot for slowing their plane. Do they know why? I'm not sure how many remember that we don't even have flaps when we select 1.

So what would be a really good beer question?

  • In flight when you select flaps one, how many flaps come out? Answer…. ZERO.
Thanks for the great question Daniel!

Enjoy the Journey!

XOX Karlene


  1. How abrupt is the change from position 1 to 2+F on arrival at whatever speed is normal? Is it enough to cause some passenger discomfort?

  2. Thanks for another good one, Karlene. One more example of why the pilot needs to know the complete function of every switch and lever - including background interactions with other systems. That seems to be your mission and it is one worthy of a snappy salute! I have no idea who originated the idea, but, "...the best way to master a subject is to teach it to another..." Thanks, professor and Happy New Year.

  3. Hi David, excellent question. No... this plane there is nothing abrupt the computers know and manage the mass. Also...there is no flaps 2+F. +F is special to the flaps 1. Identifying either we have slats only at Flaps 1. Or we have slats and flaps... 1+F. Thanks for the great comment!

  4. Thank you Craig! That's one of my goals this year. Master this plane by teaching it. Hope you will enjoy the study guide when it's complete. Happy New Year to you too!

  5. Hey thanks for posting this! What a neat system. Do people often use 1 during approach or do they get quickly to 2? Do you know if other airbus models work the same way? I get tripped up on a seemingly simple system on the boeing because slats come out at different times between the different variants of the airplane. Beyond that, things like flaps 30 equate to degrees on some and very much not on others. Thanks again for the answer!

  6. Daniel, you are so welcome for the answer. Everyone just selects flaps 1 first. There is a reason Airbus wants the slats first, perhaps just for an easy transition? I'll make a few queries about that. I haven't flown a lot, so not sure if anyone out there is just going to 2. If they are, I haven't seen it. My theory is, you must treat this plane like a woman. Don't over stress her. Take your time to get her to do what you want. Same thing with the Boeing. Don't memorize the degrees... just learn how she behaves with different configurations. Thanks for the comment!


Thank you for your comment! If your comment doesn't appear immediately, it will after I land. Enjoy the journey!