# Traffic pattern questions

JTH First Officer

Hi all.

I was practicing flying the traffic pattern today with my C172 - taking off, flying straight for about 5 miles, then requesting a full stop landing and then conduct the landing as per ATC (left downwind etc). There are a few questions I would like to ask though:

1) How far should you initially fly on the runway heading after takeoff (upwind leg)? I tuned in the ILS of the runway so the distance would come up on the DME.

2) Should you keep this same distance from the runway during the crosswind, downwind and base legs?

3) At how high above the airport should I fly the pattern? And how long would it normally take to climb to that velocity (i.e. if it's 1500ft above the runway, should I be at the 1500ft by the crosswind, or even the upwind leg?)

Thanks a lot in advance for any help clearing this up! JTH 🙂

## 3 Responses

Tailhook Chief Captain

This might shed some light on your questions ➡ http://avstop.com/AC/FlightTraingHandbook/AirportTrafficPatterns.html

Don Wood Guest

The article in the link in the post above is a good explanation of how traffic patterns work but it does contain one error. In the US, the traffic pattern altitude for light aircraft is 800 feet AGL. For heavier a/c, it is 1,000 feet AGL as stated.

Fluying straight out for 5 miles takes you well outside the traffic pattern. The technique I use in my C-172 to remain in the pattern for touch and goes or for landing is to fly on runway heading until I reach 400 feet AGL. At that point, I make a 90 degree turn to the crosswind leg. I remain within about 1 mile of the runway and make my 90 degree turn to downwind. At some point in this process, I will reach 800 feet AGL. At that point, I level off and reduce power to 2000 RPM. That will maintain level flight at 80 knots.

I continue on the downwind until I reach a point abeam the touchdown point on the runway. If I am going to use flaps for the landing, I put in the first notch of flaps abeam the touchdown point, reduce power to about 1000-1500 RPM depending on my a/c weight, and crank in about 3 turns of nose up trim. That will begin the descent for landing.

As the end of the runway is over my shoulder at about the angle I can turn my head comfortably and still see the end of the runway, I turn to base leg and put in another notch of flaps. As I begin to reach the extended centerline of the runway, I turn to final and put in the final notch of flaps. This results in putting me on final about 1 - 1.5 miles from touchdown. I then continue on to the landing. During this process, each additional notch of flaps will reduce my airspeed by about 5 knots, resulting in a speed at flare of 65 knots.

At all points in the pattern, I put in enough crosswind heading correction to keep my pattern at the desired distance from the runway.

With this technique and assuming I correctly judge the power setting for descent depending on the a/c weight and wind conditions, I can usually fly to my desired touchdown point and land without any other reductions or additions to power setting until I pull off all the power for the landing flare and without any further adjustment to trim.

This technique also works in the Sim C-172 but, for some reason, it requires an extra 200 or so RPM compared to the real a/c. It is also harder to judge the correct point to turn from downwind to base due to the lack of depth perception on the sim screen and the need to adjust the view in the virtual cockpit to see the end of the runway.

Michael_H First Officer

Really nice job on that explanation of flying the standard traffic pattern Don.

Glad you mentioned the difficulty/difference in doing this in the sim C 172. This is one of those procedures that I think is easier to do in the real aircraft.

All times are GMT Page 1 of 1