St. Louis Flying Club Newsletter - 18 November 2001

From The President - By Mike Piccirilli

Dear Members,

I want to thank Randy, Marlin and John for changing the oil, lubricating the starter, and doing some other minor squawk repairs (see maintenance section). Even with the starter lubrication, the starter still fails to engage occasionally, possibly when it is colder out. Randy suggests that we might just have to break down and buy a new one (about $400). John read an article in a Lycoming maintenance letter that suggests removing the starter and cleaning the accumulated gunk out of it. I'm all for trying that but if it doesn't fix it I authorize a purchase of a new one. I don't like the idea of members resorting to hand-propping, though given the choice of sitting or flying I'd probably do the same.

Randy called to see how I would feel about buying another plane with the improvements we've been looking to make on ours (i.e. better paint, newer radios, built-in intercom, in-panel GPS, etc.). I'm all for it but always thought that a plane in that condition would be priced comparably to ours, plus improvements, so why bother. Randy knows another FAA inspector that might just have such an aircraft. It is a Piper Warrior, close to our 172 vintage. Personally, I don't have any problem with a Warrior over a C-172 as I learned in Piper's and would look forward to a change of pace. Randy has yet to personally see the Warrior but will do that shortly and let us know if it is worth pursuing. I'm interested in your feedback on this option.

Happy Landings!
Pic

Treasurer's Report - by Marlin Sipe

Nothing significant to report on the Treasury. All reserve account levels are still looking good.

Medical/BFR Status - by Todd Michal

My records indicate that Mike Piccirilli has a BFR due in November and Mike Russell has a medical due in November. Please provide me your new BFR/medical dates so I can update my records.

   Maintenance - by John Heilmann & Randy Skyles

Maintenance Report - Randy, John and Marlin closed all of the know squawks on the aircraft on October 25th. The following actions were completed:

1. Changed the oil and filter and added a can of Avblend.
2. Cleaned and rotated the spark plugs.
3. Sprayed contact cleaner into the push-to-talk switch. Operational check indicates switch now operates without any problem.
4. Lubricated the starter drive so it will engage engine during starting.
5. Check strut servicing and cleaned strut.
6. Replaced missing screw in engine cowl.
7. Replaced missing tire stem cap on the RH main gear tire.
8. Lubricated the lock on the baggage door. NOTE: It is difficult to lock the baggage door when it is closed. The best way to lock it is to lock the door while it is open, and then push the door closed.
9. Removed the # 1 digital Radio and replaced it with the old Narco 11A Com. A radio check of the Narco 11A COM with ground control shows good transmittion and reception. When transmitting to ground control on the # 2 radio, ground control told us that the transmittion was weak and barely audible. You could hear ground control loud and clear on the Number 2 radio.
10. The digital radio was sent to the manufacturer for repair. They have received the radio but no word yet on the cause of the problems we've been having.

Owner Advisory - We received Owner Advisory number SEB95-3R1A from Cessna dated 17 September notifying us that a flap support and roller inspection is required within the next 100 hours or 12 months. The contents of the letter are as follows:

The final rule AD just released by the FAA requiring the repetitive inspection and replacement, if necessary, of the map light switch covers and chafed or otherwise damaged fuel lines does not apply for our aircraft. The AD, 2000-CE-26, is affective on models 172N and up and does not affect our model (172M) or serial number.

Oil Analysis - The Oil Analysis results from the oil change on October 25th were received and are shown below. All the values were reported as normal although the silicon (dirt) level has increased the past two times. I sent an e-mail to Aviation Oil Analysis to see what would be considered an abnormal value of silicon for our engine and received the following reply:

The high reading of silicon could be caused by the new air filter and air filter seal assembly we had replaced at the last annual inspection. We will monitor the silicon reading after the next oil change to see if the level drops. This is the first analysis we received since using Avblend and it seems to be working as the levels of wear metals in the oil sample (especially the chrome level) have dropped. Hopefully this trend will continue.

Cold Weather Operations - by John Heilmann

The following article (with some editing) is reprinted with permission from the "Lycoming Flyer" and provides some good information on cold weather operations. Although the weather the past few weeks has been great, cold weather is not far off. An interesting point is Lycoming's recommendation to preheat the engine anytime the temperature is at 10 deg or lower.

This article includes tips and information on preflight, starting, in-flight safety, and engine operational considerations. This material deals with normal cold weather operation experienced at temperatures to -25 degrees F, and not the extremely low temperatures that may be found in Arctic regions. Operation in those regions may require more specialized knowledge.

In cold weather, preheat is a factor that must be considered prior to starting the engine. There are specific guidelines in Textron Lycoming service instructions which establish when preheat should be used, but how much, or the method of preheat is generally left to the good judgment of the pilot or maintenance person doing the preheating. Use of the heated dip stick is not recommended by Textron Lycoming, although most other methods are considered to be satisfactory. For most Lycoming models, preheat should be applied anytime temperatures are at 10 degrees F or lower. The exception to this rule is the 76 series models that include the O-320-H, and the O/LO-360-E. These engines should be preheated when temperatures are below 20 degrees F. It is recommended that these guidelines be followed even when multi-viscosity oil is being used. In addition to hard starting, failure to preheat the entire engine and oil supply system as recommended may result in minor amounts of abnormal wear to internal engine parts, and eventually to reduced engine performance and shortened TBO time.

Water is one of the most likely contaminants of aviation gasoline. The engine will not run on water, and although we may get away with small amounts of moisture in the fuel during warm weather, flight into freezing temperatures makes any amount of moisture in the fuel system very critical. Even a tiny bubble of moisture may freeze in the fuel line and totally cut off the flow of fuel. Two steps should be taken to avoid this problem. First, avoid water contamination if possible. Keep fuel tanks full to prevent condensation, and be sure fuel caps do not allow leakage if the aircraft is parked outside in rain or snow. Second, look for contamination before every flight by religiously draining fuel tanks and sumps.

If flight is planned for bad weather, the preflight inspection should include observation of the relief opening in the engine breather tube so that any freezing of moisture at the end of the breather will not result in a loss of engine oil.

Once on board the aircraft, check the fuel selector valve for freedom of movement. It may be frozen fast (this has happened) and you’d better find it out while still on the ground.

Most of the time, we think of starting any engine as a very simple process. Just engage the starter and listen for the engine to start purring. Unfortunately, when the weather turns cold it is not always that simple. When dealing with a reciprocating aircraft engine, it may be essential to get a start on the first try in order to avoid icing over the spark plugs and making an immediate start impossible. In order to achieve a start on the first try, there are a number of factors to be considered as follows.

Although it might be good procedure to use an external power source for starting during very cold weather, most of us expect our battery to do the job. We should remember that the battery is handicapped by cold weather. Particularly when a single viscosity oil is being used, the colder the temperature, the more cranking energy required. Combine this with reduced battery output at lower temperatures and it can be a serious handicap.

While on the subject of batteries, remember that freezing temperatures provide a perfect opportunity to destroy an aircraft battery. The battery with a full charge survives nicely, but one that is discharged will freeze. Once this happens, the problem can only be remedied by replacing the battery, so it is very worthwhile to take preventive measures. Should the battery be run down during an attempt to start, do not leave it; get it charged immediately. And finally, be absolutely certain that the master switch is always OFF while the aircraft is parked between flights. If left on, the battery will discharge and freeze. These rather minor mistakes can be quite expensive.

Oil is another factor to be considered in the cold weather starting process. All oils are affected by temperature and tend to thicken as the temperature drops. The engine may be reluctant to turn over when the oil is stiff; a summer weight oil is not suitable in cold weather. It is also the condition which brings out the primary advantage of multiviscosity oils and of preheating. Because multiviscosity oils are thinner (lower viscosity), they allow the engine to be turned over more easily. The easier and quicker oil flow also promotes faster lubrication of internal engine parts when the engine does start.

Probably the most important factor in starting an engine is achieving a fuel/air mixture that is satisfactory for combustion. Since the engine usually starts very easily, many pilots are unaware of or ignore the change of starting procedure needed to successfully start under varying temperature conditions. In warm weather the air is less dense and therefore must be mixed with a lesser amount of fuel than in cold weather. In addition to this, in warm weather the fuel will vaporize readily and make starting easier. Simply stated, as temperatures go down it becomes more and more important that we have a plan for priming that will achieve the correct fuel/air mixture.

When priming a carbureted engine, the pilot’s plan must consider the temperature, the number of cylinders which have priming lines installed, and the number of strokes of the primer needed to produce the correct fuel/air mixture. The primer lines are ordered or installed by the airframe manufacturer and not all aircraft are configured the same. Some aircraft have actually been produced with only one cylinder being primed, and these engines are extremely hard to start in cold weather. The number of cylinders that are primed must be considered since the total fuel delivered by the primer will be divided and sent to these cylinders. As the air becomes colder and denser, the amount of prime used must be increased, but the number of strokes to be used should be planned as a result of some trial and error experimentation for each aircraft a pilot flies. When the correct number of primer strokes for each temperature range has been established, the engine will usually start very quickly. We may find that an engine starts easily when one stroke of the primer is used in the sixty-degree range, two strokes in the fifty-degree range, three strokes in the forty- degree range, etc. This is an example of the trial and error we might use to establish the number of primer strokes to use under any particular temperature condition.

The fuel part of the fuel/air mixture may be the part we have the most control over during the engine start, but keep in mind that the amount of throttle opening does have an effect on the air that is pumped through the engine. Just as we compensate for cold/dense air by adding more fuel for start, it may also be appropriate to reduce the air part of the mixture when the temperature is very cold. For example, if the throttle is normally set open one half inch for warm weather starting, it may be helpful to reduce this to one quarter inch in cold weather. Again, it will require some experimentation to determine what is needed to achieve the correct fuel/air mixture for any particular aircraft at any temperature range.

When an engine does not start easily, it can be frustrating. Of course this can occur at any time of the year and it is very tempting to just keep grinding away with the starter in an attempt to get it going. Should this happen to you, RELAX. Take care of that starter or it may fail. The general rule for starters is that they should only be operated for short periods, and then allowed to cool. If engine start has not occurred after three, 10-second periods of operation with a pause between each, a five minute cooling off period is required. Without this time limit for operation and an adequate cooling off period, the starter will overheat and is likely to be damaged or to fail completely.

Assuming the engine has kicked off, check for an indication of oil pressure. Learn the characteristics relative to response of oil pressure indications of your aircraft/engine combination. On most single engine aircraft an almost immediate response is noted.

After start, do not idle engine below 1000 RPM. It’s not good practice to idle engines below 1000 RPM at any time. This is particularly true during cold weather to prevent lead fouling of spark plugs.

A tip for every pilot, don’t run one set of fuel tanks nearly dry before switching tanks. Switch with plenty of fuel remaining in the tanks first used. This is "money in the bank," should you find the selector valve frozen.

Although carburetor ice is not necessarily a wintertime phenomena, a check of carburetor heat should be made during the engine run-up. Generally speaking, we can say that carburetor heat should never be used for takeoff, but there is one exception. This exception occurs when operating in temperatures so cold that application of carburetor heat produces a rise in RPM. Most pilots will never find themselves in circumstances which require use of carburetor heat for takeoff and climb; those who fly carbureted engines will almost certainly have occasion to use carburetor heat during cruise or let down. Use of the full hot or full cold position is recommended. An intermediate setting should only be selected if the aircraft is equipped with a carburetor air temperature (CAT) gage.

Engine operating temperature is another item that is not usually given enough consideration in cold weather. We usually are very cautious about high oil temperature which we know is detrimental to good engine health, while a low oil temperature is easier to accept. The desired oil temperature range for Lycoming engines is from 165 degrees to 220 degrees F. If the aircraft has a winterization kit, it should be installed when operating in outside air temperatures (OAT) that are below the 40 to 45 degree F. range. If no winterization kit is supplied and the engine is not equipped with a thermostatic bypass valve, it may be necessary to improvise a means of blocking off a portion of the air flow to the oil cooler. Keeping the oil temperature above the minimum recommended temperature is a factor in engine longevity. Low operating temperatures do not vaporize the moisture that collects in the oil as the engine breathes damp air for normal combustion. When minimum recommended oil temperatures are not maintained, oil should be changed more frequently than the normally recommended 50 hour change cycle. This is necessary in order to eliminate the moisture that collects and contaminates the oil.

And finally, power-off let downs should be avoided. This is especially applicable to cold weather operations when shock cooling of the cylinder heads is likely. It is recommended that cylinder head temperature change not exceed 50 degrees F. per minute. Plan ahead, reduce power gradually and maintain some power throughout the descent. Also keep the fuel/air mixture leaned out during the descent. If an exhaust gas temperature gage is installed with a normally aspirated engine, keep it peaked to insure the greatest possible engine heat for the power setting selected; for a turbocharged installation, lean to peak during descent unless otherwise specified in the Pilot’s Operating Handbook, or under conditions where the limiting Turbine Inlet Temperature would be exceeded.

Exposure to snow, frost and cold weather while flying requires the consideration of many factors, both airframe and engine related. This discussion deals with issues relating to the engine. While there may be other issues, those items which are asked about most frequently have been discussed. Safer flying and longer engine life could result from careful consideration of the material addressed.

Upcoming Safety Seminars - by John Heilmann

The following Safety Seminars and Meetings are planned in the St. Louis area in the next few months:

• Thursday, Dec. 6--Florissant Valley Community College-- 7 to 9 P.M.

  The AOPA Air Safety Foundation will be in the St. Louis area to present a program on Spatial Disorientation. The seminar will be held at the Florissant Valley Community College, 3400 Pershall Road, at the Student Center Building, Multipurpose Room. To get to the College, exit I-270 at either West Florissant Avenue or Elizabeth Avenue. The Student Center is about in the middle of the complex.

• Jan. 19, 2002 -- Boeing, Building 33-- 8AM to 1PM

  The 27th annual St. Louis and Southern Illinois Super Safety Seminar will be held at Boeing building 33, at the corner of Lindbergh and McDonnell Boulevards. Doors will open at 7:30, and coffee and donuts will be served.

FAA Private and Instrument Test Questions

See how much you remember from your FAA Private Pilot and Instrument Rating Written Test by taking a quick 10 question test. Submit your answers and you will receive the correct answers and your score. (Don't worry, only you see the test results and your score.) This is a quick and easy way to keep familiar with the FARs. Use the links below and try to get a 100%:

• Private Pilot Questions
• FAA Instrument Test Questions

The links above take you to Kip's FAA written Test Preparation Site. This site can be found directly at: http://w3.one.net/~kip/faatest.html

PAST NEWSLETTERS - Newsletter Archive

Copyright © 1999, St. Louis Flying Club, All rights reserved. Last updated 18 November 2001.