The purpose of the rectangular course is to give you a chance to fly the airplane while your attention is directed outside. As you learned the Four Fundamen- tals, you concentrated on the airplane and only noted its reference to the ground as a whole. Now you’ll begin to use the plane and make it follow a definite path over
the ground. During the first few minutes you’ll feel as frustrated as a one-legged man in a kicking contest.
This maneuver consists of flying a rectangular pat- tern around a large field or fields and is done for three reasons:
1. To get into the habit of flying the plane while divid- ing your attention between the cockpit and objects outside.
2. To learn to correct for wind drift in flying a straight course in preparation for cross-country flying.
3. To get practice in low precision flying in prepara- tion for traffic pattern flying.
The rectangular course is done at 600 feet because mistakes are easily seen at that altitude, and it builds confidence to fly at a lower altitude.
The instructor will try to pick a field lying so that the wind is blowing diagonally across it. This will give you practice in wind correction on all four legs (Figure 10-5).
Chapter 10 / Elementary Precision Maneuvers 10-5
Figure 10-5. The rectangular course is normally done at 600–1,000 feet above the surface.
Procedure
Enter the pattern at a 45° angle, flying downwind (point 1). It is easier to set up your first correction downwind because drift can generally be seen more easily. This is just a human foible, but it works out that way. The turns around the field can be made either to the left or right. Assume in this case that the turns are to the left (Figure 10-5).
Roll out of the turn at what you think is the proper correction angle. The plane’s distance from the field should be far enough away for the boundary to be eas- ily seen and yet not so far away that your mistakes can’t be seen. About 600–800 feet from the boundary would be a good distance for the average lightplane. Some students roll out parallel to the boundary and then make the correction, but it’s advisable for you to get into the habit of making a correction as soon as possible.
Assume that at point 2 you undercorrected and the plane is drifting into the field. Make a balanced turn of a few degrees into the wind and see how things fare. If
you are now holding your own and are not too close to the field to see the boundary without straining, fly the plane to the end of the field.
At point 3 you’ll have to make a left turn. Since there is a quartering tailwind, it will tend to push you away from the field, particularly if a shallow turn is made (point 4). The best thing, then, is to make a fairly steep turn at this point. The steepness of bank will depend on the wind velocity — the greater the wind velocity, the steeper the bank. Roll out of the turn with whatever correction you think necessary (point 5). Don’t count on having the same angle of correction as you had on the other leg. The wind probably won’t be crossing this leg at the same angle. As shown in the diagram, the wind is more from the side here, so more correction is needed. The vector of the wind pushing you into the field on the first leg was not as great as the vector tend- ing to move the airplane away from the boundary on this second leg.
10-6 Part Two / Presolo In the second leg, the wind is still somewhat behind
the plane, so when you get to point 6 you can figure on another fairly steep turn. This turn will not be as steep as the one at point 3 because the wind component on your tail is not as great as it was at point 3.
Your angle of bank (the steepness of the turn) is directly proportional to your speed over the ground. So the bank at point 3 (Figure 10-5) is the steepest, and at point 7 is the shallowest.
Continue the rectangular course. At point 7 the bank must be shallow because you are flying into the wind (your groundspeed is low). At point 8 the first part of the turn is shallow, then it is steepened to keep the plane at the correct distance from the field.
Start the turn when you arrive even with the corner.
(You are looking directly down the line at the next side of the rectangular course as you start the turn.) If you are crabbing (left or right), the lateral, or wing, axis will not be pointed down the next side at the point of turn. Make shallow or steep turns as necessary. (See earlier discussion.)
Probable Errors
1. Poor wind drift correction — not setting up correc- tion soon enough.
2. Not recognizing drift or not making a firm correc- tion after recognizing it.
3. Not maintaining altitude. Most students tend to climb in a rectangular course — there are a few rug- ged individualists who lose altitude.
4. Coordination problems. Some students who make perfect turns at higher altitudes get so engrossed in watching the field that their turns are awesome spectacles indeed.
5. Not anticipating the required angle of bank based on the current groundspeed. Using too much bank on the upwind turns and too little on the downwind turns.
S-Turns Across a Road
S-turns across a road, like the rectangular course, are good maneuvers for getting you used to dividing your attention between the airplane and the ground. The pri- mary purpose, however, is to show you how to correct for wind in a turn. There was a brief introduction to this idea in the rectangular course, but S-turns give you a chance to acquire finesse.
S-turns are a series of 180° turns of about a quarter- mile radius using a road as nearly perpendicular to the wind as possible. (This is for planes of 90 – 95 K cruise.
Faster planes will use a greater radius.)
The reasons for S-turns are:
1. To fly the airplane while dividing your attention between the cockpit and the ground.
2. To learn to correct for wind drift by varying the bank. This will come in handy later in circling and remaining near the same spot in a strong wind.
3. To get practice in precision flying in preparation for advanced maneuvers later.
S-turns are also done at 600 feet for the same rea- sons as those given for the rectangular course.
The object is to fly a series of semicircles of the same size, making smooth balanced turns and correct- ing for wind drift by varying the steepness of the bank.
The plane should cross the road in a level attitude with the wings parallel to the road.
Procedure
A road that runs as nearly 90° to the wind as possi- ble is picked. It is best to enter the S-turns downwind, because drift is more easily detected and corrected by the student if correction requires a steepening of the bank rather than shallowing it out. The first turn can be made in either direction.
As shown in Figure 10-6, the initial bank must be steep; otherwise, the wind would “push” the plane too far from the road before the turn is completed (point 1).
Assuming that you have set the correct steepness of bank, when point 2 is reached the bank must be shal- lowed or the plane would be turning at the same rate of turn in degrees per minute, but as it began to head into the wind, the groundspeed would drop. It would appear to “pivot” and would not follow the smooth curve of the semicircle but would end up at point 3.
The shallowing of the turn should be such that the wings are level as the plane crosses the road, still at 600 feet (point 4).
After you cross the road, the bank should be a shal- low one in the opposite direction. If a steep bank is used, a path such as at point 5 would result.
When point 6 is reached, the bank must be steep- ened in order to have the turn completed as the plane crosses the road again. If the bank was not steepened at point 6, a path like that of point 7 would occur. The plane would not cross the road at the correct place nor would the wings be level or parallel to the road.
Continue the series until you get tired or run out of road. Remember: The angle of bank is directly pro- portional to the groundspeed. (The greater the ground- speed, the greater the angle of bank.)
Chapter 10 / Elementary Precision Maneuvers 10-7
The angle of bank in S-turns must be constantly changing. The hardest part of trying to keep the maneu- ver smooth is at point 8, where you have to roll from a steep bank one way to a steep bank in the opposite direction.
If the wind is strong, many students do not have a shallow enough bank on the upwind side of the road, and the airplane drifts into the road. Strangely enough they are able to correct on the downwind side without much trouble. Many times in this situation the plane’s path over the ground looks like Figure 10-7.
One problem with these maneuvers is that you may spend all of your time looking at the ground references.
You should keep an eye out for other traffic as well.
AIM Chapter 8 has some good information on collision avoidance procedures.
Probable Errors
1. Failure to properly correct for drift.
2. Rolling out of the turn too soon or too late, resulting in crossing the road with wings not parallel to it.
3. Gaining or losing altitude.
4. Coordination problems in the turns (jerky or slip- ping and skidding).
In the S-turn you are interested in a definite path over the ground and therefore must correct for the movement of the air mass of which you are a part.
Figure 10-6. S-turns across the road.
Figure 10-7. A common error in S-turns across the road.
10-8
11-1 At some time during the period of rectangular courses
or S-turns, your instructor will demonstrate an elemen- tary emergency landing or “simulated emergency,” as you may hear it called.
Engines nowadays are very reliable. Cases of engine failure are rare, but you will still be given emergency- landing practice because pilots still run out of fuel and leave oil caps off. It is still possible, too, that the engine could fail structurally, so it’s better to be prepared.
The elementary emergency is given below 1,000 feet and requires a 90° gliding turn at most. The instruc- tor will pull the carburetor heat and close the throttle at some point during the maneuvers and demonstrate the procedure.
If it is at all possible, you want to land into the wind. If the plane stalls at 50 K and you have a 15-K headwind, your groundspeed (or relative velocity to the ground) at touchdown will be 35 K. The advan- tages of this are obvious. However, sometimes a field may not be available for an upwind landing. Or if the field is steeply sloped, it’s better to land uphill even if it’s downwind. Obstacles may require that you land downwind.
Sometimes students who’ve been doing the rectan- gular course or S-turns for several minutes and have
been correcting for a stiff wind forget the wind direc- tion as soon as the throttle is closed for the simulated emergency.
Picking the right kind of field (at low altitude you don’t have much time to shop around) comes with experience. If you’ve lived on a farm, you can spot a good field without much trouble.
Table 11.1 is a list and description of various types of fields with comments about each type.
Obviously there will be times when some of the landing spots labeled “poor” and “very poor” will be the only ones available. It then becomes the case of making the best of a bad situation. As one instructor put it, “Hit the softest, cheapest thing in the area as slowly as possible” — which pretty well covers it.