traffic pattern for turbines: how wide for the downwind?

NoHeat

NoHeat

En-Route
Joined
Jul 27, 2009
Messages
4,990
Location
Iowa City, IA
Display Name
Display name:
17
I can't find anything in the FAA books that says how far from the runway a turbine will normally fly, on the downwind leg. I can only find this, in the AFH:

The downwind leg is a course flown parallel to the landing runway, but in a direction opposite to the intended landing direction. This leg is flown approximately 1/2 to 1 mile out from the landing runway and at the specified traffic pattern altitude.​

But if a turbine can fly 1500' AGL and 200 KIAS in the downwind, it's gotta need a wider base, right?

I'm wondering how just how wide is typical, after seeing an Embraer 450 landing in front of me - it flew a downwind that was 2.8 miles wide (I measured it using this track on the FlightAware).

IMG_6833.jpg
 
I was following a Falcon the other night that was CTL runway 34 at PWK, they grazed the ORD bravo on their base leg… close enough that tower called them on it.

67B01995-DA1F-4EFD-8E2C-ADCFB32DDAED.jpeg
 
An airplane flying at 200 knots will need to be 2 nm from the runway for a standard turn base, no straight run in the middle.
 
As wide or narrow as the PIC feels is comfortable and workable, depending on if it's a King Air or a swept wing jet.
 
Turbine aircraft flying a pattern? Nah! Straight in at 180 knots, no flaps, no gear, calling a 10 mile final and transmitting ... "traffic in the area please advise and be advised - caution wake turbulence!"

I hear that's the way they do it in a piston twin ... :D
 
My opinion?

n9GeKhy.png
 
In a 737, I'll be wide enough that you won't think I'm even in the pattern. 200kts on downwind, 170 on base, target on final which could be anywhere in the 145 to 165 range, depending on weight and wind.
 
Last time I flew a pattern in the CRJ200, it was wide enough to allow a base to final turn that was 15-20 degrees of bank and 160 knots in order to put us on a five mile final. OpSpecs won't allow us to cut the corner any closer or make it any tighter than 5 miles. We have to be fully configured and stabilized by then or it becomes a go-around/missed approach.

Bottom line, it just depends on the aircraft and operation type (91, 91k, 135, 121, etc, etc...).
 
flight2000 said:
Last time I flew a pattern in the CRJ200, it was wide enough to allow a base to final turn that was 15-20 degrees of bank and 160 knots in order to put us on a five mile final. OpSpecs won't allow us to cut the corner any closer or make it any tighter than 5 miles. We have to be fully configured and stabilized by then or it becomes a go-around/missed approach.

Bottom line, it just depends on the aircraft and operation type (91, 91k, 135, 121, etc, etc...).
Click to expand...

Just curious, which OpSpec are you referring to?
 
I don't think he meant standard RATE...just a standard...or "typical" turn
Guessing that's what you were referring too, since I did a double take on that one.
 
One of the arrivals I frequently do puts us on a 4.2sm (3.7nm) downwind, which is actually on the tighter end of the range. On visual approaches with no arrival I usually shoot for a downwind around 4-5 miles because overshooting final is a big :no::no:
 
kaiser said:
I was following a Falcon the other night that was CTL runway 34 at PWK, they grazed the ORD bravo on their base leg… close enough that tower called them on it.

View attachment 111117
Click to expand...
You should see the CATerpillar guys doing that in the Global. It's a sight.

On the straight in at 150 kts, it's all about TIME more than distance. 2x the speed = 2x the distance.
 
flight2000 said:
Last time I flew a pattern in the CRJ200, it was wide enough to allow a base to final turn that was 15-20 degrees of bank and 160 knots in order to put us on a five mile final. OpSpecs won't allow us to cut the corner any closer or make it any tighter than 5 miles. We have to be fully configured and stabilized by then or it becomes a go-around/missed approach.
Click to expand...
That's not a pattern, that's maneuvering outside the pattern for a straight in. Just watch out for C-152s turning base in front of you... :eek2:
 
As wide as I need that when I turn base to final to be around a 5-7 mile final.
 
Lindberg said:
Who does standard-rate turns in the pattern?
Click to expand...

Brad W said:
I don't think he meant standard RATE...just a standard...or "typical" turn
Guessing that's what you were referring too, since I did a double take on that one.
Click to expand...

@PaulS referred to a 200 knot turn taking about a 2 mile diameter, meaning from downwind to final with no leveling the wings for base. That's a correct estimate for a standard rate turn.

However, a standard rate turn at 200 ktas takes just shy of 30 degrees of bank. So I'd say in Paul's example of 200 kts, most operators would be flying at LESS than a standard rate turn.
 
@ those pattern distances how would you ever make the runway if you lost an engine? :rolleyes:o_O
 
Yup, that was the estimate for a standard rate turn with full radius, no straight path in between. From what I see flying in a busy delta, the bigger planes generally come. when on the downwind, at least a few miles from the field, at 1500 agl, fly out at least a few miles, then turn from downwind to final. They are moving, you don't want to be headed toward them if they call a 3 mile final.

I'm generally less than standard rate on my turns in the pattern, primacy for me, I had a 1 year check after I got my license and had gotten comfortable with 35 to 40 degree turns (probably more) in the pattern. My instructor at the time tsk'd me and said I was going to kill myself. I took that to heart.
 
Mxfarm said:
@ those pattern distances how would you ever make the runway if you lost an engine? :rolleyes:o_O
Click to expand...

Yup, you won't make the runway approaching the airport most of the time you are flying too.
 
E42F13C2-9D51-4C6F-839B-86776CB73311.jpeg Well, just today I was in a turbine in the pattern.

I try to hit 3/4mi abeam at 5k’. I turn at the numbers. Maintain 160kts until the flare, touch down at 50 kts. The VSI is pegged and indicates only 3k fpm, it’s probably closer to 5…

If I lose an engine, the dumb prop auto feathers and I got problems!!

You were taking about turbo prop jump planes, right?
 
In a 737, I'll be wide enough that you won't think I'm even in the pattern. 200kts on downwind (I'll need flaps to go that slow), 170 on base, target on final which could be anywhere in the 145 to 165 range, depending on weight and wind.
 
1/8 mile at 600'
PXL_20220824_183335011.jpg
 
PaulS said:
I'm generally less than standard rate on my turns in the pattern, primacy for me, I had a 1 year check after I got my license and had gotten comfortable with 35 to 40 degree turns (probably more) in the pattern. My instructor at the time tsk'd me and said I was going to kill myself. I took that to heart.
Click to expand...

And just why would that be?

As long as you are flying coordinated turns with the proper airspeed, you can fly 60 degree banked turns in that pattern.

That was normal for the USAF VFR.
 
Pinecone said:
And just why would that be?

As long as you are flying coordinated turns with the proper airspeed, you can fly 60 degree banked turns in that pattern.

That was normal for the USAF VFR.
Click to expand...

He was probably trying to keep me from killing myself? I don't know, and have no reason to doubt him, especially with the number of pilots who have spun it in.
 
Many of those deadly accidents were because the pilot didn't fly a coordinated turn, for one reason or another. Some additional margin to a stall/spin is generally warranted at pattern altitudes, but standard rate in a C150 might be a bit overkill.
 
Pinecone said:
And just why would that be?

As long as you are flying coordinated turns with the proper airspeed, you can fly 60 degree banked turns in that pattern.

That was normal for the USAF VFR.
Click to expand...

With an approach speed of 1.3 Vs0, and a 60 degree bank resulting in stall speed that is 1.41 times higher than normal, you would be incorrect.
 
Larry in TN said:
In a 737, I'll be wide enough that you won't think I'm even in the pattern. 200kts on downwind (I'll need flaps to go that slow), 170 on base, target on final which could be anywhere in the 145 to 165 range, depending on weight and wind.
Click to expand...
If you're 5 miles away on downwind as some are suggesting, then no, I don't think you're in the pattern.
 
dmspilot said:
With an approach speed of 1.3 Vs0, and a 60 degree bank resulting in stall speed that is 1.41 times higher than normal, you would be incorrect.
Click to expand...
That's for a level turn. Why would you be flying a level turn from downwind -> base or base -> final? And isn't 1.3 Vs0 the "over the fence" speed?
 
Lindberg said:
That's for a level turn. Why would you be flying a level turn from downwind -> base or base -> final?
Click to expand...

I didn't say anything about being level so no, that was not part of my argument. The load factor goes up in a descending turn just as much.

Lindberg said:
And isn't 1.3 Vs0 the "over the fence" speed?
Click to expand...

Don't know what "over the fence" means, but 1.3 Vs0 is a typical approach speed, and turns are typically part of an approach.
 
Last edited:
PaulS said:
He was probably trying to keep me from killing myself? I don't know, and have no reason to doubt him, especially with the number of pilots who have spun it in.
Click to expand...

Have you ever spun out of doing a steep turn????????

Does you instructor have ANY idea what causes a spin?
 
dmspilot said:
With an approach speed of 1.3 Vs0, and a 60 degree bank resulting in stall speed that is 1.41 times higher than normal, you would be incorrect.
Click to expand...

DUH, I did say PROPER airspeed. Proper airspeed means for the conditions of flight, which includes the bank angle.

Oh, and that 1.4x stall speed is for a LEVEL turn.

But I guess the USN and USAF have NO idea what they are doing and crash a lot in the traffic pattern.
 
dmspilot said:
I didn't say anything about being level so no, that was not part of my argument. The load factor goes up in a descending turn just as much.
Click to expand...
I’d say “just the same” as opposed to “just as much”, but I talk funny so maybe we’re saying the same thing.

Stall speed is about load factor. An aircraft in a 1g 60* bank turn has the same stall speed as an aircraft in a 1g 20* bank turn. The difference would be the vertical component of lift, thus the 60* aircraft would be in a descent (course would also be different).
 
flight2000 said:
Last time I flew a pattern in the CRJ200, it was wide enough to allow a base to final turn that was 15-20 degrees of bank and 160 knots in order to put us on a five mile final. OpSpecs won't allow us to cut the corner any closer or make it any tighter than 5 miles. We have to be fully configured and stabilized by then or it becomes a go-around/missed approach.

Bottom line, it just depends on the aircraft and operation type (91, 91k, 135, 121, etc, etc...).
Click to expand...

I know it’s subjective, but can we all just agree that if you are outside of the boundaries of typical class D airspace, you aren’t ‘in the pattern’???
 
Pinecone said:
Have you ever spun out of doing a steep turn????????

Does you instructor have ANY idea what causes a spin?
Click to expand...

I don't really understand your point, I suspect for most people who have spun in the pattern and died, it was their first time..... and last.

That was my primary instructor, and yes he would regularly spin train students, I'm pretty sure you have to understand spins to teach them. In fact he had a student put a plane into an incipient spin base to final, which he saved. He had seen at least one massive screw up and what precipitated it. So I absolutely trust what he says over some guy on the internet berating pilots who don't do steep turns in the pattern.

I'm not an ace pilot, I don't need thrills in the pattern, in fact I work to keep my patterns mundane. If I get to the point where I need a 60 degree turn to correct things, I just power up, go around and try again. You do you, I'll do me. There are no medals for banging around a pattern.
 
You must log in or register to reply here.
Back
Top