As a long-time subscriber and consumer afficionado, I thought your article on the new Exxon Elite oil was interesting and exciting. I have had two adverse experiences with this oil worth relating. I was introduced to Elite at Sun n Fun in April and was given a free case.
I used two quarts immediately in my 1967 Mooney Executive 21 with 800 hours on the rebuilt engine. The flight back home was eventful in that the weather required me to climb to 11,000 feet.I went through the usual leaning procedures and had an uneventful flight until the night landing. Since I was high, I powered back. But on landing, I ballooned and had to give back some power to smooth out the landing. At this point, I heard a knocking sound.
I removed my LightSPEEDs to better hear it. On inspection, the crankcase was covered with oil. My mechanic started the engine in the morning and it ran, albeit poorly. We found cylinder attach bolts on the pavement. The only thing possibly contributing was a loose induction pipe on the front left cylinder. I only had a single EGT probe mounted on the right rear cylinder and never saw over temps on the EGT, oil temp gauge or CHT gauge. Since the airplane had just come out of annual, I chalked it up to overlooking the loose induction tube. End of story, until a flight out to Colorado in my 1969 Aztec.
I noted high temps on the right engine.Since this is a high-time engine-1800 hours-and it was burning more oil than the left, I was adding more Elite to the right engine. We had taken off from and after less than an hour, put down. After de-cowling the engine and going over it, we could find nothing wrong.
My mechanic suggested adding more oil and flying with 11 quarts instead of 9 1/2 and we did that, with an uneventful flight. On the way home, however, after flying forfour hours with the temperature on the right engine 30 degrees higher than that of the left, the right prop governor went crazy. I couldnt get it to hold a constant speed, so I landed in Dyersburg, Tennessee.
When I checked the dipstick, it was almost too hot to touch. After a cool down, we again de-cowled the engine and checked the nitrogen load on the prop, which was within limits. Because it was about time for an oil change, we changed the oil and filter.We used Aeroshell 100 single-weight oil. The mechanics comment was, boy, that oil looks thin.
I decided to fly home, less than three hours away. The oil change cured the problem. With 40 hours on that oil change, Ive had no problems with the governor and the oil temps have been reasonable.
When my mechanic called Exxon to investigate, he was initially blown off. But on suggesting that a call to the FAA might be in order, he gotan urgent call from one of the chief engineers. An interesting comment: Was this by any chance a high-time engine? The engineer seemed to imply that there had been problems with high-time engines. Despite the hype, Exxon will not be the oil supporting any of my aviation engines.
-Robert D. Hagberg
Steve Sunseri of ExxonMobil told us the company was aware of reader Hagbergs experience and was investigating it. Thus far, no findings have emerged because the company has been unable to examine the engine.
However, Sunseri said he knows of no other such incidents involving Elite and prop governors on high-time engines.
By far the best oil filler gadget seems to be one not mentioned in your August 2000 article. Its a disposable funnel made of oil-resistant cardboard. Ten of these come in a flat pack, selling for $1.75 at our FBO. They fold easily into a funnel strong enough to hold the weight of a full bottle of oil and can be discarded afterwards with no mess.
The Disposable Funnels, No. 1007, are made by TOR Manufacturing Co., P. O. Box 721, Chester, Virginia 23831-0721, 804-796-5110. I have enclosed a picture showing a disposable funnel in action on top of the cowling of my TB20.
No doubt each of us has a pet method for the oil change/add mess, heres mine: I think its somewhat better than your article suggestions.I have an old M20D Mooney, with a well tucked away Lycoming oil filler.
A supermarket provided a black plastic filler about 10 inches long (no brand markings) that screws onto an oil bottle. Right next to the bottle screw is a flex bellows section that permits inserting the spout into the filler before tipping the bottle to pour oil. This eliminates the need for a shut off that will eventually break or get set wrong.
It fits into the filler with the dipstick still in the hole. Its about 10 years old and no cracks. Maybe 15W50 is good for plastic!
This requires squeeze and release of the bottle until its light enough for the bellows to hold it up, then leave it until you get tired of it draining to the last drop. Maybe a piece of 3/4-inch Tygon on some short spout would do the same thing. Now to differ on the messy part. Plastic bags? Ugh! I have a cardboard box about 8 X 10 inches that holds three oil bottles, the Meguires for the windshield and a bug sponge with a cleaned out, well-labeled oil bottle of water.
Also in the box is a two-pound coffee can with two plugs and a wrench, screwdriver, water pump pliers, dykes and safety wire. In this can is a soda can with the top out and paper towel in the bottom for the oil spout; no mess!
A paper towel wadded into the top of the spout keeps it clean and there are no lids to lose or to drop into the filler hole.
The chamois and big sponge go on top of the box in a plastic grocery bag. The roll of paper towels holds it all down. I know a rag is better, but the windshield wasnt new when I got it 15 years and 2300 hours ago and it hasnt shown any change since then.
Everything fits tight in the box, cant tip and hasnt bounced out yet no matter how hard my head has hit the overhead.
Singles Vs. Twins
I have just read your article comparing heavy singles with light twins. I believe you omitted two factors that may favor light twins.
First, night flight in the best of conditions may well be safer in a twin than in a single. Second, the twin can carry radar without degrading performance and without a penalty in icing situations either.
Ive flown quite a bit with radar and Stormscope in the same panel. In dirty situations, the Stormscope is a poor second best to good radar.
I admit to a certain prejudice. Ive had three engine failures in twins, although only one was an honest engine problem. The latter was a reduction gear failure in a twin Bonanza.
The others were a fuel valve problem in an Aztec, a problem later repeatedly addressed by ADs, and an uncommanded feathering of a propeller in a P-Baron.
Since I was able to make safe landings on airports all three times, one of them night IMC (T-Bone), I lean heavily towards twins when I have the opportunity.
-Michael S. Green
We didnt omit those factors. We believe they qualify under the general rubric of perceived safety. Both radar and de-ice are safety-of-flight items that may or may not actually contribute to safety.
As we noted, the bottom line is the bottom line. The main driving factor remains money, in our estimation. If you can afford to own and operate two motors, the rest is merely rationalization.
I enjoyed your article on Heavy Single or Light Twin? However, I think you missed what is perhaps the best justification (or is it rationalization?) for choosing the light twin over the heavy single.
If, as a pilot, youre planning on advancing later to faster aircraft, the next step up from the heavy single or light twin is the medium twin, something in the Cessna 414/Beech Duke/Aerostar class.
These planes offer amenities like 220-knot cruise speeds, known-ice certification, pressurization, air conditioning and over-the-weather capabilities that are available in few (if any) singles.
Unfortunately, its nearly impossible for a pilot with low multi-engine time to get insured in these aircraft. Thats why if youre planning to continue moving up, the light twin is the way to go.
Big Bear Lake, California
Your article in the August Aviation Consumer regarding Heavy Single vs. Light Twin was very good. As an owner of a heavy single (1976 Piper Lance) that flies over the water to the Bahamas a lot, I looked to making the switch myself.
My mechanic, an honest gentleman and an owner of an Aztec, was the one to talk me out of it. He pointed out the huge increase in operating and maintenance cost and the doubling of the probability of an engine failure.
I have, however, a concern with your understanding of statistics. You state that given the inaccuracy of the hour estimates, a dose of skepticism is in order.
This is a true statement. Unfortunately, you continue by stating its reasonable to assume that hours estimates for both twins and singles are equally suspect so the relationship may very well be valid. This is not a true statement.
When you compare two inaccurate (high variance) values, the inaccuracy of the comparison increases (sum of the variance of the original values) rather than decreases. If they are equally suspect, their comparison will have twice the uncertainty or twice the probability of being invalid.
I had an Avidyne installed in my twin a few months ago. In summary, I made a mistake. The unit is not user friendly. I am quite computer literate and had problems operating the soft keys. They are not intuitive, in my view.
The instruction manual doesnt help that much, either. It took me 10 minutes of fiddling the first time I had to usethe radar function. As far as the charts go, they are virtually unreadable unless used at the lowest scale, like a mile across the entire screen.
Finally, while the Navigator mode does produce a clear and large picture, it does not display half the informationof the much smaller Argus. I understand that the factory does have new software that will improve the maps.
Also, the overlay feature will be nice once the factory develops that software.
I am sure I am in the minority because I have spoken to a few who do like the unit. Of course, those are pilots who never had a moving map before.
The next time I try something new, I will wait for it to be developed a bit better and wait to read about it in your magazine.
-Name withheld by request
While we agree that early adopters do pay a price, we dont agree that the Avidyne is difficult to use, although well defer to your comments on the radar function, since we didnt try that feature.
To its credit, Avidyne has upgraded all of its early users to the latest software improvements. In general operation, we found the Avidyne to be quite manageable, especially compared to the typical desktop IBM PC.
Western Skyways in Montrose, Colorado gets good marks with the Cessna Pilots Assocation.
Why was it not included in your survey?
The trouble with write-in surveys is that if no one writes, the sheet is blank. Such was the case with Western Skyways, were sorry to report.
We received no comments about this shop, although we did in a previous engine survey. We agree that it has a good reputation and were sorry we overlooked mentioning the shop. Well cover it next time.