Control Tower - December 1999

Merry Christmas, and a Happy New Millennium!

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FINAL ISSUE OF THE MILLENNIUM!

I want to thank Jim Bourke for his dedication to electric flight that produced this web magazine, and for his willingness to turn the reins over to me to guide it into the new Millennium.  Thanks, Jim!

 

New Items

I'm pleased to offer this special Christmas issue of the E-Zone - one of the larger issues we've put out to date.  Be sure to look at the new KidZone column by Gabe Baltaian.  This new column and some of our reviews will be focused on showing kids and newcomers in action with electric flight, hopefully encouraging more newcomers to join the ranks of electric flyers.  You'll also find a review on the Easy Sport 40 in this issue, by one of our younger pilots. 

Here are some of Gabe Baltaian's comments regarding his new column:

 KidZone Preface

 

While there are many reasons for the lack of involvement of kids in model aviation (expense, lack of transportation to a flying field, lack of time) there are at least two of them that we can do something about:

1 – A few decades ago aviation was constantly in the headlines for flying faster / higher / better. Nowadays most stories dwell on noise, terrorism, crashes or delays, with the net effect of showing aviation to be either dangerous, boring or both. Fortunately for us, the EAA has started a whole range of very good programs to remedy this problem and I think that their efforts can work hand-in-glove with r/c flying in general and especially our clean-and-quiet electric airplanes.

2 – There are relatively few age-appropriate role models for kids. If you open up an r/c car magazine you’ll notice that the average age of the people pictured is several decades lower than it is for the airplane mags. I expect that if more kids are shown flying, competing, building and designing airplanes it will have a positive effect on the hobby’s ability to recruit new younger members.

I would like to use the new KidZone column to help get the word out about any activity that presents modeling and / or aviation in a positive light so as to get kids interested in it. I also want to use the column to be a showcase for the efforts of anybody up to the age of 21 who’s involved in model flying (hopefully, but not exclusively, electric). I’ve assembled a wide range of materials for the first column that I hope you’ll take a look at. Also, if you have kids who are involved in flying in any way, please send me any info and pics you’d like to see included in future columns.

 

Battery Life

Bob Kopski's electric airplane column in the January 2000 issue of the AMA Model Aviation magazine presented an interesting thought regarding battery life that seems to parallel my own experience.  I had a number of 1700 mAh cells arranged in 10 cell packs that began to go bad prematurely this past summer.  They were constantly false peaking, and individual cells were refusing to take a charge at all at an alarming rate.   Since they were made up of surplus cells, I attributed their seemingly short life to the cells.  However, I had a number of 1200 mAh cells that were still going strong after years of hard running and abuse (I gained most of my electric flight experience using these cells).  Aside from the type of cells, the most significant factor seemed to be that these cells were always run in 6 - 8 cell configurations, and usually as 7 cell packs.  Pat Mattes suggested at the time that the problem might be the relatively low cutoff of my brushed controllers for running higher cell count packs.  The three brushed controllers I have been using all have motor cutoffs at around 5.5 volts.  On the other hand, my brushless controller looks at the initial voltage of the pack and sets the cutoff point at half the initial voltage.  Either way is no problem when running 7 cell packs.  It's generally suggesting that battery packs should only be discharged down to 0.9 volts per cell.  With a 5.5 volt cutoff, you've discharged a 7-cell pack down to slightly under 0.8 volts per cell - not far off the "ideal" 0.9 volts.   However, if you are running 10 cells down to the cutoff point, you're bringing the pack down to 0.55 volts per cell.  If your cells are mismatched matched any significant amount, you run the risk of reversing cells and harming the pack. 

As a result of Pat's suggestion, I'm either running my newer packs with the brushless motor/controller when using higher cell counts, or cutting the motor as soon as it begins to lose power and not discharging the packs any further.  This was the heart of Bob Kopski's comments as well.  Bob noticed that while his packs were going bad, his friend's packs were staying like new, and the only difference was that his friend didn't discharge his packs all the way down to the cutoff point.  He simply stopped the motor when the power dropped off and recharged the batteries.  As a result of these findings, Bob redesigned his controller to have a variable cutoff point, allowing him to tailor the cutoff for various battery cell counts.  Sounds like a great idea to me!

 

Mars Airplane - Great Opportunity for Electrics?

The most recent issue of the Smithsonian Air and Space magazine had an article on NASA' proposals to fly an airplane on Mars.  Wouldn't that be a great opportunity for electric flight - perhaps even with solar cells?  Who will be the first to fly F5B on Mars?

 

Inside Hobby Lobby

I told you about my visit to Hobby Lobby International in the June issue of the E-Zone, but I didn't have any pictures to show you at the time.  I was able to make a return visit (they happen to be located near my in-laws) during the Thanksgiving break, so I thought I would bring you a few images of the facility.  As before, Jim Martin and Kevin Butts were very gracious hosts, and there were plenty of interesting things to see.  If you are ever down that way, be sure to drop in and say "hi". 

 

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Here are the people who make Hobby Lobby happen.  On the right is Jim Martin, the owner of Hobby Lobby International.  On the left is Kevin Butts, Jim's right-hand man.  Two of the nicest people you would ever want to meet!

 

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Here's a little look inside the store.   On the left is the retail store, where you can walk in to buy products.   Lots of neat things to see!  In the middle is one of several rows of products behind the scenes.  Those are bins full of esc's, motors, gearboxes, etc., all ready to be packed up and shipped somewhere.  On the right are some of the offices of the people who handle the phones and all the other details that go into running the business.

 

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Just a glimpse of some of the interesting offerings of Hobby Lobby International.  On the left is the Miss 2, a geared Speed 400 ARF park flyer.  No it's not electric, but I thought it would be fun to show this offering: in the center, an ARF indoor rubber powered plane!  On the right is a unique ARF Fokker Triplane slow flyer.  They make it easy to have fun with e-power!

 

Longster Wimpy

Recently I showed an image of a Longster Wimpy taken at a nearby fly-in.   That plane probably generated more interest than any other plane I've shown here.  So, when I saw one of our local fliers, Ralph Kiester, flying one at the local club's Toys for Tots fly-in I had to get a few photos and some information.  Ralph's plane was built from plans published in the AMA Model Aviation magazine's August issue.   He powers it with a geared Astro 035 on 10 ,1400 mAh cells and a 10x6 prop (I believe it's a Master Airscrew wood electric prop).  Ralph used two sub-micro servos for the ailerons, and a pair of micro servos for the rudder and elevator.  He says the Wimpy weighs in a 51 oz - pretty trim for a 10 cell ship!  It certainly does seem to fly nicely.

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Reader Mail

Two thoughts on clubs, AMA membership

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From: fatman(at)erols.com
Subject: A Modest Proposal
Date: Wed, 24 Nov 1999

 

Dear Sir,

This summer I converted to electric powered R/C aircraft.  It opened up a new vista to what R/C modeling can be; small planes that load into your car ready to fly, the ability to use any type of paint for delicate scale finishes, not having  to tote a huge pile of support equipment to the field. I also have found a "independent club", four oilies and one e-power fellows who, for whatever reasons, don't care to join the local AMA sponsored clubs. Which brings me to the point of this email.

I don't think that most e-power fliers need or want the AMA.  Most electric planes would not cause much damage and the type of flying field requirements would be much more flexible.  Almost any open field could support an e-power runway which could be a 4'X40' sidewalk. This would be quite affordable for several people.  I have been a member of the AMA while flying i/c models because I understand the damage that could occur from a out-of-control model. Unfortunately i/c power clubs (generally) consider electric planes as "toys" or "novelties". The AMA field that I fly at is quite uncondusive to electric planes. You have to carry the plane  (due to the grass runway and taxiways) about 60' to the runway and the surrounding trees create wicked turbulence until you get above 200'.

Where I live (Northern Virginia) land is at a premium. I predict that the old style, i/c based R/C clubs will be pushed out by  development. I see a need for electric only clubs that can operate in suburban areas near populated communities. Most non-modelers find the electric R/C planes much more "friendly", as opposed to noisy models with a chainsaw motor spinning a finger chopping prop.  I know I wouldn't want a 1/3 scale Extra doing 3D junk over my  house!

Thank you for your time

Travis K. Ballou

 

 

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From: Elizabeth&Tex Gehman <eliztex(at)sprint.ca>
Subject: Frequency Control
Date: Sat, 04 Dec 1999


Steve: I've been in R/C airplanes for 25 years, many of them using electric power. I've noticed a lot of change, most for the better, but there is a very disturbing evolution within the ranks of E-flyers.  I have the impression that many of the ab-initio e-fliers have not been instilled with a suitable regard for the safety of others, in that they are flying their planes in isolation, and not in affiliation with a club, or group. I infer that some are not members of AMA, or in my case MAAC, and in fact might never have heard of these organizations. This in itself is not a bad thing, but both of these modelers associations have set guidelines for the safe operation of miniature aircraft.   Separation of venues is one of them and that goes hand in hand with control of frequencies to avoid conflict.  I continually read that people are flying in parks, school yards and even in streets. Who of these type of person has ever done anything to verify that they are operating with a dedicated frequency? This is the reason for having a "surface" frequency band, so that those who want to operate their vehicles or boats in a non-controlled environment will not cause a disastrous accident with an airborne model, or just as bad, one that is being started or is taxiing.
I also fly giant scale gasoline powered models, some worth many hundreds of dollars, weighing 20 or 30 pounds. Imagine what damage or injury some inconsiderate non-hobbyist toy airplane operator can cause by indiscriminately turning on a transmitter!  I hope that you as an editor will consider the seriousness of the ever expanding laxness and begin to educate your readership about the responsibilities incumbent with being associated with this great sport.

Yours truly

C. W. (Tex) Gehman
Winnipeg, Canada.

 

I'll have to partially agree and partially disagree with each of these notes.  It's a neat idea to start an e-power club, but it's still a good idea to keep AMA membership (or equivalent).  There are plenty of E-planes that can cause serious damage.  On the other hand, I enjoy flying out of isolated schoolyards and parks, but I also agree that safety should be first priority.  Be sure to check for others operating planes in your region, and fly with the AMA guidelines in mind. 

Unhappy Customer

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From: "Robert P. Damjanovich" <bobd(at)cybermesa.com>
Subject: Dymond L-19 Bird Dog
Date: Mon, 06 Dec 1999


E-zoners:

I wish Paul Bradley's review in the September mag had been published in August. I might have saved quite a bit of aggravation and quite a few bucks.

Being a newbie to electric flight and to RC, I decided to order a "package deal" to get a starter outfit that would all work together.  The L-19 seemed like a good idea, and when I queried Dymond, they (of course) agreed. I ordered the plane plus their "super" accessory pack.

I finally got the outfit almost 4 weeks later (out of stock problems) and by then I was into heavy work travel, and didn't get it ready to fly until Thanksgiving.

With the Dymond recommended 1400mAh 7-cell pack, the plane weighs 752 g (~26.5 oz) with radio. With the supplied motor and prop screaming away, the first launch resulted in a javelin-like trajectory! We re-checked the CG, re-adjusted the prop (which had been shoved into the airplane by the lawn dart landing) recharged the battery pack, and tried again.   Same result. On the third try the propeller gave up the contest with the sod, and I'm now awaiting a replacement.

I doubt that the airplane will ever fly reasonably here-- we're at a base elevation of 2200 meters (7200 feet) above sea level--but I specifically asked about that when I ordered.

Oh well, even if the plane won't fly, I can use the radio, servos, batteries, etc. in a lighter plane. Sigh.

More on the order problem: When I made the order, I (stupidly, in retrospect) asked to upgrade the charger in the accessory package. No problem, I was told, we'll just charge you for the difference between the standard and the upgrade. Fine. Let's add in a extra battery pack, too, since I'm being optimistic. OK.

My error. Since all was not in order, I got the standard plane, with the upgraded charger and the extra battery pack. I didn't get the ESC/BEC that was part of the super pack. I was (fairly) charged for *what I got,* but I didn't get what I ordered.

After more than a month of trying to deal with Dymond, getting e-mail apologies, promises and excuses, I gave up and assembled what I had. By that time Dymond had wisely decided that they were spending way too much effort on an unhappy customer, and I haven't heard from them since.

 

 

The Christmas Story

I've asked our columnists to share their thoughts on Christmas in this issue if they so desired, so I'm going to do the same here.  This is not e-flight related.   Rather, I wanted to take a more personal approach and share a Christian perspective on the real meaning and joy of Christmas. 

  Christmas Thoughts

 

Do you ever dread the arrival of Christmas? It seems like everyone is running around stressed, crazy, and generally discontented. It's been said that people at Christmas spend money they don't have to give gifts they don't need to people they don't like. However, the real story of Christmas is very different; it's the story of the One who gave the greatest gift He had for people in desperate need whom He loved dearly. It's the story of how we can have that deep, inner peace that rises above circumstances (and what to get Aunt Martha). It's the story of absolute confidence that you can face whatever the future holds, because you know who holds the future.

Of course, I'm talking about God's gift of His son, Jesus Christ - the Christ of Christ(mas). So often the Christmas story stops with the virgin birth, the baby in the manger, the wise men, the star in the East, and the shepherds. All of which is significant, particularly in the fulfillment of Biblical prophecies (like Isaiah 7:14 and Micah 5:1-5). If you stop with the baby in the manger, however, you've really missed the heart of the message. Christ didn't leave the glories of Heaven and put aside certain aspects of his deity (Phil. 2:5-11) just to come to earth as a baby - he actually came to earth as a man to die in our place. The unfortunate truth is that everyonel has sinned and offended God (Rom. 3:10, 11, 23), who is holy and perfect. The just punishment for sin is death (Rom. 6:23) - separation from life, and separation from God. Since "no one is perfect", no one could stand before God on their own merits. Christ therefore came to earth to live the perfect life that no one could (Heb. 4:15), and then to die in our place and take our punishment. It's somewhat like being brought before a judge in a court for breaking the law; you're guilty, and it doesn't matter how many good things you've done or how long you've lived a good life - you're still guilty of breaking the law. You deserve to be punished. However, imagine that the Judges' son suddenly intervenes and says "Dad, let this man go free - I'll serve his sentence for him". It's almost unthinkable. Justice would be done, yet mercy would prevail. This is the gift God gave us in Christ. We can't earn it, and we can't pay for it (Eph. 2:8,9). It comes by admitting to God that you have offended Him, asking for his forgiveness because Christ took your place, and asking Him to take control of your life. Then He pours His life into you, and you truly become a "new creation" (2 Cor. 5:17). This is where the real joy of Christmas is found!

I hope that this Christmas you'll receive all kinds of electric goodies - planes, motors, chargers, batteries, etc., - but don't forget the most important gift of all, the only one that will last beyond death and into eternity.

Merry Christmas!

Steven Horney
E-Zone Editor

 

Planes should be seen and not heard.  Pour on the Watts!

Steven Horney
E-Zone Editor

shorney(at)ezonemag.com

 

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