Please note: James' blog has moved to a Wordpress site. To access it, please visit http://jameswiebe.wordpress.com/. All posts have been transferred to the new site, and all new posts will only be accessible via Wordpress. Thank you for your interest!
A few days ago, I posted information on how to calculate the Center of Gravity in a Belite taildragger ultralight airplane. Today, I provide an update for tricycle gear aircraft.
You should review my original post, here. After you review it, consider the following example for a tricycle gear plane.
Note that the nose wheel has a NEGATIVE arm, as it's distance is negative from the firewall. All other arms are positive. Remember to weigh the aircraft with an empty fuel tank; add the fuel and the pilot weight as shown in the equations as below.
Center of Gravity, Tricycle gear ultralight aircraft calculations:
DESCRIPTION, WEIGHT (in lbs.), ARM (in inches), MOMENT (lbs x inches)
Front nose wheel, 70, -5, -350.
Main wheels, 180, 49, 8820.
Pilot, 200, 39, 7800.
Fuel, 30, 56.6, 1695.
Total weight is 480.
Total moment is 17965 (-350+8820+7800+1695)
ARM of the aircraft is 17965 / 480 = 37.42"
This aircraft is in the CG range.
REMEMBER, you must measure the actual ARMs of your ultralight airplane using a plumb bob from the firewall, and the aircraft must be level. (This may be a little easier to do in a tricycle gear plane, as the plane is mostly level to begin with.)
I hope you find this useful, no matter what kind of aircraft you fly.
"The Standard Pilot Blog"TM The Chipper and Radiant Blog for Experimental and Ultralight (Part 103) Aircraft (c) 2010 thru (c) 2020 by James Wiebe.
Wednesday, April 18, 2012
Sunday, April 15, 2012
What is the world's lightest aircraft?
Please note: James' blog has moved to a Wordpress site. To access it, please visit http://jameswiebe.wordpress.com/. All posts have been transferred to the new site, and all new posts will only be accessible via Wordpress. Thank you for your interest!
I'm asking: what is the world's lightest airplane?
I'm not asking what is the world's smallest: that honor may be held by this airplane, the Bumble Bee II. Read about it on Wikipedia.
The Bumble Bee II is definitely not light, weighing in at 396 pounds. Any Belite is lighter than that.
But Guinness points to an aircraft called the Wee Bee as the world's lightest. (I find the name Wee Bee very interesting!)
You can read about it here, and they claim it had an empty weight of 210 pounds. It looks fairly fatal, because the pilot rides on top, face first. Any accident is going to be a killer:
The 1949 Popular Science article this photo is taken from is a must read.
And it's a Wee Bee. Just can't get over that.
A Belite can be built with a weight of 210 pounds. But Belites are definitely not the lightest planes in the world: what about the Easy Riser, of John K Moody fame? It weighed a little more than half what our planes weigh.
And also, what about various Human Powered Aircraft? These have been around quite awhile. Here's a pic of one, in flight:
So I'm really asking: what is the world's lightest, gasoline or electric, human carrying airplane with an enclosed cockpit?
Here are the rules:
1) Must be gasoline or electric. (Disqualified Human Powered, which weigh less than 100 pounds...)
2) Must have an enclosed cockpit. (Disqualifies the WeeBee)
3) Must be fairly conventional: wings, engine, tail, or canard. (Disqualifieds weird stuff, like balloons.)
I'm asking: what is the world's lightest airplane?
I'm not asking what is the world's smallest: that honor may be held by this airplane, the Bumble Bee II. Read about it on Wikipedia.
The Bumble Bee II is definitely not light, weighing in at 396 pounds. Any Belite is lighter than that.
But Guinness points to an aircraft called the Wee Bee as the world's lightest. (I find the name Wee Bee very interesting!)
You can read about it here, and they claim it had an empty weight of 210 pounds. It looks fairly fatal, because the pilot rides on top, face first. Any accident is going to be a killer:
The 1949 Popular Science article this photo is taken from is a must read.
And it's a Wee Bee. Just can't get over that.
A Belite can be built with a weight of 210 pounds. But Belites are definitely not the lightest planes in the world: what about the Easy Riser, of John K Moody fame? It weighed a little more than half what our planes weigh.
And also, what about various Human Powered Aircraft? These have been around quite awhile. Here's a pic of one, in flight:
 |
| Human Powered Gossamer Condor, in flight |
So I'm really asking: what is the world's lightest, gasoline or electric, human carrying airplane with an enclosed cockpit?
Here are the rules:
1) Must be gasoline or electric. (Disqualified Human Powered, which weigh less than 100 pounds...)
2) Must have an enclosed cockpit. (Disqualifies the WeeBee)
3) Must be fairly conventional: wings, engine, tail, or canard. (Disqualifieds weird stuff, like balloons.)
Brand New Simonini Engine for sale!
Please note: James' blog has moved to a Wordpress site. To access it, please visit http://jameswiebe.wordpress.com/. All posts have been transferred to the new site, and all new posts will only be accessible via Wordpress. Thank you for your interest!
The spring cleaning sale at Belite continues....
At Belite, we officially support a couple of different 2 stroke engines: Hirth (German) and Compact Radial Engines (Canadian). Another type of engine that we took a look at a long time ago was Simonini (Italian). I decided not to support this engine type in the Belite. I believe they are very popular for some other markets (for instance, Powered Para Gliders...).
So I am offeirng a brand new Simonini engine for sale. I *think* it is a Simonini Mini 3, which you can read about here. After I purchased it, we never started it up. (Simoni makes several different engine models which look similar).
I'm offering it without reserve. It will be a really great deal for someone. I see that Simonini is offering this engine at the new price of $4144.
Starting bid is $25. This engine will be posted for sale on eBay.
The spring cleaning sale at Belite continues....
At Belite, we officially support a couple of different 2 stroke engines: Hirth (German) and Compact Radial Engines (Canadian). Another type of engine that we took a look at a long time ago was Simonini (Italian). I decided not to support this engine type in the Belite. I believe they are very popular for some other markets (for instance, Powered Para Gliders...).
So I am offeirng a brand new Simonini engine for sale. I *think* it is a Simonini Mini 3, which you can read about here. After I purchased it, we never started it up. (Simoni makes several different engine models which look similar).
I'm offering it without reserve. It will be a really great deal for someone. I see that Simonini is offering this engine at the new price of $4144.
Starting bid is $25. This engine will be posted for sale on eBay.
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| Simoni Engine for sale |
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| Simonini Air Filter |
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| Simonini Carburetor |
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| Simononi exhaust manifold |
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| Simonini motor mounts |
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| Simonini Muffler mounts |
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| Simonini Muffler |
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| Simonini redrive |
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| Simonini Muffler mount |
Monday, April 9, 2012
Calculating Center of Gravity in a Belite Ultralight Aircraft
Please note: James' blog has moved to a Wordpress site. To access it, please visit http://jameswiebe.wordpress.com/. All posts have been transferred to the new site, and all new posts will only be accessible via Wordpress. Thank you for your interest!
It's easy to calculate the Center of Gravity in a Belite Ultralight Aircraft!
*** NOTE: This post is for taildraggers. I have posted an additional blog entry on how to calculate CG in a tricycle gear airplane. After reading this taildragger post, you can read the additional post on calculations for a tricycle gear plane HERE. ***
1. Ensure that the aircraft has everything on board that should be in place for finding the empty weight and CG. Using a level, put a support under the tailwheel and make sure that the plane is level front to back and side to side. You'll need to lift the tailwheel off the floor by somewhere around 20 inches. The lower door line may be used as a level line. Here's what a level Belite looks like:
2. With the aircraft level and all fixed equipment installed, record the scale readings and weights. The fuel tank should be empty.
Right Wheel = ____________ Pounds
Left Wheel = ____________ Pounds
Tailwheel = ____________ Pounds
3. Verify and recalculate as necessary, the ARMs for each wheel location. This is done relative to the forward face of the firewall. You can use a plumb bob from the firewall to mark the location on the ground, then measure back to the middle of the main wheels and the tailwheel.
Typical Main Wheel ARM = 20.6 inches (yours may vary)
Typical Tail Wheel ARM = 162.6 inches (yours may vary)
We also need to know where the pilot is located and the fuel tank. For our sample airplane, we will assume 36.9 inches for the ARM of the pilot, and 58.6 inches for the ARM of the fuel. You are encouraged to verify these ARMs as well.
4. Now let's do some calculations on weights, ARMS, and moments. We'll add in the pilot weight, and also the weight of some fuel.
Weight, ARM, moment
Right Wheel 124.7 x 20.6 = 2568.8
Left Wheel 124.7 x 20.6 = 2568.8
Pilot 200.0 x 36.9 = 6273.0
Fuel 30.0 x 58.6 = 1758.0
Tailwheel 28.2 x 162.6 = 4585.3
And let's add up the weights and moments:
In this example, the weight adds up to 507.6 pounds (with gross aircraft weight of 550 pounds, so that's good) and the moments add up to 18861.0.
Dividing total moment by total weight, 18861 / 507.6 = 37.16. This means that the CG is 37.16 inches. Since our aircraft has a range of 34.5 to 39.1, we are good to fly.
5. Further exercises.
You'll want to determine CG at a variety of pilot weights (to match your own weight) and fuel conditions. In our example airplane, the CG is 35.81 at a zero fuel condition, so the CG moves forward as fuel is consumed.
It's easy to calculate the Center of Gravity in a Belite Ultralight Aircraft!
*** NOTE: This post is for taildraggers. I have posted an additional blog entry on how to calculate CG in a tricycle gear airplane. After reading this taildragger post, you can read the additional post on calculations for a tricycle gear plane HERE. ***
1. Ensure that the aircraft has everything on board that should be in place for finding the empty weight and CG. Using a level, put a support under the tailwheel and make sure that the plane is level front to back and side to side. You'll need to lift the tailwheel off the floor by somewhere around 20 inches. The lower door line may be used as a level line. Here's what a level Belite looks like:
 |
| Belite Ultralight Airplane, Level, Side View |
2. With the aircraft level and all fixed equipment installed, record the scale readings and weights. The fuel tank should be empty.
Right Wheel = ____________ Pounds
Left Wheel = ____________ Pounds
Tailwheel = ____________ Pounds
3. Verify and recalculate as necessary, the ARMs for each wheel location. This is done relative to the forward face of the firewall. You can use a plumb bob from the firewall to mark the location on the ground, then measure back to the middle of the main wheels and the tailwheel.
Typical Main Wheel ARM = 20.6 inches (yours may vary)
Typical Tail Wheel ARM = 162.6 inches (yours may vary)
 | ||
| Measuring ARMS for CG calculation on ultralight aircraft |
4. Now let's do some calculations on weights, ARMS, and moments. We'll add in the pilot weight, and also the weight of some fuel.
Weight, ARM, moment
Right Wheel 124.7 x 20.6 = 2568.8
Left Wheel 124.7 x 20.6 = 2568.8
Pilot 200.0 x 36.9 = 6273.0
Fuel 30.0 x 58.6 = 1758.0
Tailwheel 28.2 x 162.6 = 4585.3
And let's add up the weights and moments:
In this example, the weight adds up to 507.6 pounds (with gross aircraft weight of 550 pounds, so that's good) and the moments add up to 18861.0.
Dividing total moment by total weight, 18861 / 507.6 = 37.16. This means that the CG is 37.16 inches. Since our aircraft has a range of 34.5 to 39.1, we are good to fly.
5. Further exercises.
You'll want to determine CG at a variety of pilot weights (to match your own weight) and fuel conditions. In our example airplane, the CG is 35.81 at a zero fuel condition, so the CG moves forward as fuel is consumed.
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