Full Flaps of not???

Maximilian_Jenius

Maximilian_Jenius

Super User
At a recent Phoenix meet & greet while talking to Douglas Houser M.D. and pilot602 the subject came up about full flaps on landing.

I fly commerically fairly decently and I have noticed on approach some airline pilots are making approaches & landings minus full flaps more especially on SWA.

During my PPL training I had many different instructors. Some taught ALWAYS have fully flaps in on landing others would teach to have in full flaps if the wind is calm or variable or a good tailwind. But others taugh not using full flaps if there is a strong headwind or crosswind.

Dougie Fresh and pilot602 both agreed full flaps on landing ALWAYS. I for one have always agreed with them.

So I'd like to know what other aviators think about the issue of full flap landings or not.
 
In the jets the issue of noise can come up. Full flaps will require more power than any other setting which increases the noise that the NIMBYs must hear. Also buffeting around and a rougher ride come with more flaps as does increased fuel burn for the last few minutes of every flight which adds up.

Some airlines have a last flap position locked-out via a small wire so that the crew cannot select that flap setting unless there is an emergency.
 
cal 73's land flaps 30 (not full) and lately at xjt we've been doing flaps 22 when the numbers work for the runway.

when i'm flying GA my flap setting depends on 1) where the turnoff i want to make is and 2) the speed of the traffic im sequenced with. flaps up or full flaps, doesnt really matter to me.
 
In a 172 I use full flaps most of the time...unless there's a strong xwind...then maybe only half. Strong headwind...well depends on if I need them or not.

So I guess my official answer for the question is, IT DEPENDS.:)

Glad to help.
 
It is most likely being done for fuel savings. during my last few months at my last airline management started a fuel savings program which called for flaps 22 landings and thrust reversers only at idle unless operations required flaps 45 or thrust reversers. Like was said earlier, the flaps add a lot of drag and the typical power setting for a flaps 45 landing in the EMB-145 is much higher than a flaps 22 landing. You spread that out over hundreds of flights a day and the fuel saved adds up.
 
The reason for not deploying full flaps during approach and landing is mainly due wind gusts can cause a considerable and abrupt floating action. I teach full flaps for "regular" landing conditions. With 10 knots or more of x-wind I typically use two clicks (usually 20 degrees) of flaps to 1) reduce floating should gusty conditions occur 2) increase control effectiveness as the approach speed without flaps typically allows you to carry a little extra approach speed.
 
As stated above, at our airline we use less than full flaps if we meet certain parameters. If we do not meet those parameters, then we use full flaps. The lesser flap setting gives us some minimal fuel savings, plus a smoother touchdown. It does take more runway to stop due to higher approach speeds and less drag, however.

At some B737 operators, they are also using the Flaps 30 vs. Flaps 40 choices for fuel savings and runway stopping reasons.
 
FlyChicaga said:
As stated above, at our airline we use less than full flaps if we meet certain parameters. If we do not meet those parameters, then we use full flaps. The lesser flap setting gives us some minimal fuel savings, plus a smoother touchdown. It does take more runway to stop due to higher approach speeds and less drag, however.

At some B737 operators, they are also using the Flaps 30 vs. Flaps 40 choices for fuel savings and runway stopping reasons.
Click to expand...

Thanks for the replies guys. Chicaga I remember reading a recent thread where you talked bout flaps 22 vs. flaps 45 in the ERJ.

When (and if) fuel prices job does anyone who flies for airlines think that said compaines might be less thrifty and again allow full flap landings under normal circumstances?
 
To answer your question Max, I would think not. I would hope not. In fact, I am going to say that I would highly encourage pilots to do everything they can to save fuel from now on. It is really not hard to save fuel, it just takes smart, heads-up flying. As it is now, there are still pilots who are lazy and do not care enough to save fuel.

I for one find it a challenge to try and beat the fuel numbers for each flight. It keeps me busy, and is actually fun in a way.
 
The answer is that it's a regulation:

91.126 Operating on or in the vicinity of an airport in Class G airspace.

91.126(c) Flap settings. Except when necessary for training or certification, the pilot in command of a civil turbojet-powered aircraft must use, as a final flap setting, the minimum certificated landing flap setting set forth in the approved performance information in the Airplane Flight Manual for the applicable conditions. However, each pilot in command has the final authority and responsibility for the safe operation of the pilot's airplane, and may use a different flap setting for that airplane if the pilot determines that it is necessary in the interest of safety.

And, lest you think that only applies to Class G, keep reading, each higher class refers back:

91.127 Operating on or in the vicinity of an airport in Class E airspace.
(a) Unless otherwise required by part 93 of this chapter or unless otherwise authorized or required by the ATC facility having jurisdiction over the Class E airspace area, each person operating an aircraft on or in the vicinity of an airport in a Class E airspace area must comply with the requirements of §91.126.

91.129 Operations in Class D airspace.
(a) General. Unless otherwise authorized or required by the ATC facility having jurisdiction over the Class D airspace area, each person operating an aircraft in Class D airspace must comply with the applicable provisions of this section. In addition, each person must comply with §§91.126 and 91.127.

91.130 Operations in Class C airspace.
(a) General. Unless otherwise authorized by ATC, each aircraft operation in Class C airspace must be conducted in compliance with this section and §91.129.

91.131 Operations in Class B airspace.
(a) Operating rules. No person may operate an aircraft within a Class B airspace area except in compliance with §91.129 and the following rules:
 
first off forgive the ramblings (drunk and posting)

Flaps really depend on the airplane. On the Dash8, flaps 35 (full) was required at full props (1200 rpm) so the flap setting dictated the prop setting, meaning in case of a go around with full flaps you had the power there instantly. Now on the DC8 it is flaps 50, unless it is a short body JT8 model (-62) which is 35 flaps, for noise.

In my humble opinion, even on long runways, the max flap available should be used. The fuel burn is negligible (don't drag full flaps from 15 miles out), and the savings on breaks, time on the runway, etc far outweighs any other "savings". I believe most any airplane is easier to land at less than full flaps, but that should not be a consideration.

I see a trend going toward the "hury up and get there" mentality with regards to profiles and configurations, that I think needs to be stopped and replaced with a conservative attitude. We are in the business of moving people and property SAFELY, and shortcuts have no room here. The extra .05 on the hobbs or block time, is not going to matter, when we have airplanes over running runways, or doing go arounds, etc etc.
 
seagull-- good info, thanks! regulation though. Can't really see how you could hold any enforcement action on it the way that it's worded though. It's regulatory force seems to be more of a 'suggested operating procedure'

As for the flaps/no flaps issue, I break it down into GA/Commercial like so:

If you're flying a GA aircraft, put the flaps where you want 'em, when you want 'em. If it were always best to make no-flap landings, the damn plane wouldn't have them in the first place. If it were always appropriate to make full flap landings, then you'd think there'd be a placard somewhere, right? I preferred no-flap full-slip to landings, but I come from a field where stooging around on final at 65 knots usually resulted in go-arounds for many bizjets and t-props. Not safe. Then again, if I were landing down at Lake Whitney, you can bet I was using all the flaps the little monster had! It's called good judgment, which, as good little pilots, we should all be striving to develop.

As to flaps in a turbojet, a lowered flap setting can give you a small but significant fuel savings, which is the name of the game right now with 'Bush and the Hallitones' putting the screws to gas-burning America. For example, the ERJs have two common flap settings for landing, 22 and 45 degrees. At Xjet we've been using the 22 setting for longer runways and it saves about 180-200 pounds of fuel per landing. That's about 30 gallons, at (appx.) $2.50 a gallon, times 1000 departures a day. That's $74,000 a day, $2.2 Million a month, $26.9 Million a year, and that dosen't take into account the higher gas prices that we get charged at some outstations. It's not negligible!

The arguments against the lower flap settings are: more use of TR's, more brake usage (MX cost), and longer taxi time due to longer landings. I haven't found this to be the case. There's only so many exits to a runway, and I've found that I consistently make the same high-speed exit with 22 as I do with 45, with no extra braking and no TR usage at all. So there's that.

As for safety, I find the lower 22 flap settings in the ERJ safer than 45. Here's why: Our FOM dictates that we are to be 'configured and stabilized' by 1000 AGL, which is sensible enough, and easy enough to do in a perfect flying environment. But when are things perfect? Almost never. In Newark, going 170-180 to the marker is standard. When I get there, I have to throw everything out, pull it to flight idle, intercept the slope, and then jockey it to 145 knots so I can get that last flap setting in to 45 and then stabilize the approach. Sometimes it's all done by 1000 agl, sometimes it's not, but what's scary is that I'm busy, low, unspooled, with a trend vector that's rapidly plummeting into Vso range. And as a cherry on top, the target speed set is usually at or below Vso, so when I'm trying to hold a few knots above that (1.3 Vso, as I should be doing) you get Captain Anal McUpgrade barking that I'm too fast (??!?). Nothing about any of this strikes me as safe. Or standard. Or even normal.

Contrast the 22 setting. You do 180 to the marker, call 'Gear down Flaps 22, landing cheklist' and you're done. That's all. You're configured and stabilized way above 1000 agl. Target speet is even 1.3 Vso most times. And you're about 5 knots faster, so you're not killing the Heavy behind you. And the landings are smoother, and easier to do. And if it's gusty, you're not wallowing around like a pig with the PLI jumping up and down. And if you have to do a go-around, there's less drag to contend with and no low-altitude configuration change. And your profit sharing check is a little bigger, and you have more job security. Easier, safer, saves gas. I really can't see a problem with that.
 
I was taught to never use 40 flaps and use 30 for normal landings and 20 of X wind landings.
 
As always: It depends

Our ramp is 800 or so feet from one end of a 5500 foot runway. The long way is also uphill. When playing lets make our turnoff at 800' you want everything out there sticking into the breeze ie. flaps 40 in a fwd-slip. When you've got 4700' uphill to your ramp flaps 40 and 30 is a waste especially when there is a jet on your tail. I will usually land flaps 10 and land long in those cases, flaps 20 with no traffic.
 
Hey thanks whoever said what I was thinking about a full flaps approach being only flown for the last couple mins. of the approach. I had been thinking that after reading some earlier post. I'd think that unless you were on a 5,10 mile final at full flaps you wouldn't see a signifigant fuel loss.

But what do I know. CapnJim excellent post I enjoyed reading it.

Doug,DE727UPS,Bandit Driver et,al. I'd love to hear from you guys that fly the big metal and your opinions and your companies policies on flying an approach with full or less then full flaps for fuel conservation faster approach etc.
 
I love it when guys in 172s drop 20 degrees of flap on the downwind (4 miles off of the runway) and then drop 40 flaps for base and then proceed to turn into a 8 mile final.


really makes my day.
 
I teach to only apply the last 10 degrees (last notch) once a landing is assured as it helps with go around situations.
 
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