Good Words about S-TEC
Ken Paul, Director of Marketing
We've recently gotten excellent coverage in two major aviation publications and wanted to call them to your attention.
The September Issue of Aviation International News has an excellent article written by the Dallas based Associate Editor of the magazine. Matt Thurber spent an entire day with us profiling the company and our products. You can find the article on Page 94 of the September Issue, which is the NBAA Convention Preview Issue. We've enclosed a reprint of the article with this newsletter. Additional copies are available.
A column in the September 1997 issue of Flying Magazine favorably compared the performance of an S-TEC System 55 autopilot to that found in the "front office" of a Boeing 767. Tom Block, USAir Captain and author of the regular column titled "Flying the Line", came to S-TEC when he was upgrading his Cherokee 235. We worked with him and his local S-TEC dealer as he purchased and installed the S-TEC System 55. We'd recommend making this article a regular part of your S-TEC sales story.
FLYING THE LINE
AUTOPILOTS
by Thomas BlockExcerpts with the permission of the author.
... The autopilot has become such an important part of the operating crew that, on the Boeing 767 for example, we normally have more of the electronic-pilot versions onboard than we do of the human type: three versus two. ... There are scads of operations that you aren't legal to attempt without a fully functioning set of autopilots. ...
When I was beginning to plan out the upgrades for my Cherokee 235 a couple of years ago, the issue of the autopilot came up early because the one that had come with the airplane was a single-axis unit exhibiting signs of being more dead than alive. Since I like to do a variety of things with my personal airplane, including some extensive traveling, and since I'm the same pilot regardless of whether I am sitting in the left seat of the Boeing or the Piper, I looked over the entire gamut of replacement units and what they would do for me before I made a final selection.
A single-axis autopilot - the least expensive unit - has authority over aircraft heading only, utilizing the ailerons. ... A two-axis autopilot - a more expensive choice - is one with pitch authority, and it is often in error labeled a three-axis system. A true three-axis system needs to have input to the ship's rudder, and even big jets-which do have that capability-don't use it very often. The only time the rudder is being controlled in a Boeing 767 is when a multiple-autopilot ILS approach is being performed to what is intended to be an auto landing.
... The big debate in smaller airplanes is whether adding the second axis of pitch authority is worth the expense. Lots of people say that an airplane like my Cherokee doesn't need it because it's so stable in pitch, but in my experience the airplane isn't any more stable in pitch than it is in roll.
... A two-axis system costs more to buy and more to install. Autopilots do not come cheap because they are complex units that must be carefully interfaced with the airframe. What the manufacturers must go through to get FAA approval for their units would take your breath away-and each type of autopilot must be individually approved for each airframe. On that score my hunt for a replacement autopilot narrowed quickly, because S-TEC was the only manufacturer that had the necessary FAA approvals for my airframe in the price range I wanted to stay in. Fortunately, it had the approval for a few different autopilot models.
The fact of life in single-pilot flying is that having a one-axis autopilot aboard is like having a student pilot in the right seat to help; some things are done well, others, not at all-and everything needs to be watched continuously. Add the second axis and your helper suddenly acquires a private license with an instrument rating. To me, it was worth the extra money to get that full measure up front.
... My choice had now narrowed to three models: the original S-TEC barebones two-axis Model 50, the more elaborate Model 60 or, if I wanted to go all the way, their newest unit: the Model 55.
... The S-TEC System 55 is a rate-based two-axis autopilot that combines all the necessary functions in one radio-rack-sized panel-mounted unit. It would interface fully with all my nav equipment, and even more to my liking was that it included one feature that I had become familiar with on big jets: control wheel steering. Having the S-TEC System 55 in the airplane would turn my helper from a private-with-instrument to a fully qualified ATP.
... Within an hour of the first flight, the 55 and I became good friends.
On the wide-body Boeing, I make the takeoff and initial climb manually, then reach up and punch on one of the triple autopilots sometime during initial climb. It comes to life in a mode that includes continuing the climb to whatever altitude is dialed in the panel alerter window, at whatever airspeed I was at when I told the autopilot to take over. In the Cherokee, I hand-fly around until I feel like I'd prefer some help, then I simply push the "CWS" button on the wheel. The autopilot engages itself at whatever rate of climb and angle of bank I was in-and will hold the bank forever and keep on climbing until I run out of available engine power.
An available option from S-TEC that I didn't take was altitude preselect (I did not get it because of budget and panel space, both of which were becoming tight), which the Boeing has and my Cherokee doesn't. In the 767 the jet will push itself over to level out nicely at whatever is in either the preselect window or, in certain modes, whatever is in the Flight Management Computer. In the Cherokee, I can punch the altitude hold button, dial down the vertical speed to zero, or hold the CWS button while I push the airplane level manually with the control wheel and then let go of the button again.
Navigating in either airplane is nearly identical. Give the autopilot in the Boeing or the S-TEC 55 a heading to intercept a navigational course line-VOR, ILS, inertial nav/GPS-and it will do the entire job.
... Not only do the electronics themselves do a great job, but having the automation turned on releases a great deal of the crew's focus from the task of flying to the task of monitoring. It's amazing how much more you can see of a developing situation (cross-winds, wind shear, nav flags) when your job is to watch and wait. This is now true in the Cherokee because the coupled approach setup is straightforward and the results are quite dependable.
... A go-around in the Boeing is easier because it is more automatic-but not by much. Push the go-around switch on the thrust levers and the big jet spools up and pitches up as it climbs out at 2,000 feet per minute on whatever course line you've established. Without an auto-throttle in the Cherokee, the go-around is best done as a manual affair by either disconnecting the autopilot or holding down on the CWS button. But once the airplane is safely moving upward, the 55 is immediately there for me by simply punching the CWS button in order to continue the climb and/or the turn.
... Yet the most hours spent with my new autopilot in the Cherokee are just like the most hours spent with the autopilot in the 767-up at cruise, going directly to somewhere without me having to watch the nav track and altitude at every moment.
... That's what either of these autopilots are all about-giving a little help. Both of them give a lot.
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