Powerfin Propeller: Recommended! (But choose length and adjust pitch wisely)

I've been doing some testing on a Powerfin propeller on our Superlite.  I've come to the conclusion that if properly selected, Powerfin's composite propeller provides a superior alternative to the wooden propellers which we've been using on our aircraft.  (Albeit at a higher cost.  Most good things cost more.)

Last year, I flew quite a bit with a 3 blade Powerfin propeller.  I was not happy with the performance.  In hindsight, the issue was our selection of a short 3 blade prop -- we should have tried a two blade.

And so, I had switched to inexpensive 2 blade wood propellers.  They were a good, economical solution providing reasonable performance.  Their downside is maintenance (their leading edge will erode, especially in heavy grass fields) and inability to adjust pitch.

Recently, I was contacted by Powerfin to consider the usage of their propeller with our aircraft.  We received a brand new "B" series propeller, and we bolted it onto our Hirth 50HP engine.

I wanted to know the answers to these questions:

a)  Would this propeller provide any increase in efficiency over our most ideal wooden propeller?

b)  Would this propeller allow for easier power tuning for Part 103 users?

c)  Would it look cool?

The answer to all 3 questions is yes.  Here's more of the story about efficiency and prop re-pitching:

I've done power consumption testing on the Hirth, and reported on the results in this blog a couple of months ago.  The gas consumption was 3.4 gallons per hour.  The U.S. distributor of Hirth engines suggested I might be able to improve on this fuel consumption figure; I was a little skeptical.  But the Powerfin propeller appears to have proven him correct.

To test the configuration, we selected a prop length of 65 inches, in the "B" series ground adjustable propeller from Powerfin.  This is the longest propeller I've ever thrown on our aircraft.  I thought the extra length would help with efficiency.   I then selected an initial propeller pitch using an online tool I've found which helps interpolate diameter, pitch, RPM, atmospheric conditions, and engine power.  You can find this propeller tool here.  In order to really make it work, you have to convert diameter and pitch to an angle setting for the propeller pitch.  I use this tool to perform that calculation, just put in circumference and pitch into the calculator, and it delivers an angular setting.  (For a 65 inch prop, the circumference is 204.2 inches -- you know how to do that, right?!)  [diameter * 3.142 = circumference]. 

After selecting an angle of 7 degrees, we used a prop protractor to set the propeller 'bite' or pitch, bolted all the bolts to the recommended torque values, and it was time to runup and test power.

As it turned, a quick runup and takeoff showed me that this pitch angle (7 degrees) was too much of a bite, and the engine would not rev up to full power.  In fact, not even close.  However, it was sufficient to get off the ground and allowed me to enjoy flying a grossly underpowered utralight aircraft, but not for very long.  (I landed.)

So the pitch was reset to 6 degrees, and I took another test flight.  This time, the engine was still not able to develop full power, but that's OK -- it climbed great, and was already exceeding the FAR Part 103 cruise speed limit by a wide margin.  (Cruising at 61 knots, 6 knots too fast, this is about 70mph.  If I cut the pitch angle back to about 5.5 degrees, the engine would develop higher RPM and full power, and the Belite Superlite would go EVEN FASTER (probably around 75mph cruise), but that's not my objective.  (However, it may be your objective, if you are building a Belite as an experimental N-Numbered homebuilt aircraft.)

I want to be able to cruise at exactly 55 knots -- which is 62mph, which is the FAR Part 103 cruise speed limit.  So I'll soon reset the pitch to about 6 1/2 degrees.  This should be just the right amount of power.  In other words, the adjustable pitch prop is an excellent way to fine tune a big horsepower engine to be FAR Part 103 legal.

I continued my testing of the Powerfin prop.  I started with a full tank of gas, and I cruised for an hour at exactly 62 mph, with a few takeoffs and landings mixed in.  I then landed and checked fuel consumption with a measured dip stick (I'd also been tracking fuel consumption in flight using our fairly amazing Belite fuel gauge):

Belite Fuel Gauge -- works great -- please buy one.

 
At the end of the flight, I'd used 3.15 gallons, and I had 1.85 gallons remaining.  Therefore, total time to fuel exhaustion is about 1 hour and 35 minutes -- a substantial improvement over the wooden prop I'd been using.

When using the Hirth 50HP engine and the Powerfin prop, this calculates to a range of a Belite Superlite, in FAR Part 103 legal mode, of 98 miles.

And I do like the way the Powerfin looks!

Here's some things to keep in mind:

a) The larger diameter is definitely a good thing.  However, proper technique calls for 3 point landings and careful takeoffs to avoid grass rash on the prop.  If you want a little shorter prop, I wouldn't go with anything less than a 60 inch diameter on a Belite.

b) As I mentioned earlier, good things come at a price.  These composite props aren't cheap -- but they are worth it if you want the most adjustable option combined with the most efficiency.

c) Also, they are little heavier than wooden props.

d)  I will be adding this prop to our price list.

-- James

I spotted 14 deer while loitering in the air

Short post:

I'm not a deer hunter.  I've occasionally mused on the idea; ... maybe some day.

This evening, I spotted a group of 14 deer while flying in the neighborhood of home field.  About half of them had antlers, and one was a very nice buck.  No, I won't tell you exactly where I saw them.

I made several circuits around their field, recounting and noting the number of bucks. 

Awesome.  Awesome!

Even MORE INFO on Stall Speed, Vortex Generators and Ultralight Aircraft

If you haven't been on this blog in the last few days, there are several new posts.  Don't miss the post on landing in a hayfield!...

The following is a discussion which will intertwine some stall speed testing and also some slight discussion on vortex generators.

A couple of months ago, I mentioned that I had put Vortex Generators on a Belite.  I was not able to provide much substantial information to you, my faithful reader, as to how they performed.  I'm still don't have much to offer, but I have begun to experiment with their placement on the wing.


I also recently discussed the FAR Part 103 mandated stall speed requirement of ultralight aircraft.  My blog post on that topic may be found here.


So here's a little more info.

We've had a few days of smooth air, and smooth air is absolutely intentional when performing stalls at absolute minimum airspeed.  Any disruption of the smooth air causes the plane to stall, screwing up my testing.  This is critically important when we are talking about stall speeds of less than 30mph.


Acting on a hunch related to my impression of the high angle of attack on our Riblett designed airfoil, I moved the Vortex Generators closer to the leading edge of the airfoil, which you can see here:

Vortex Generators on an Ultralight Aircraft, EG:  Belite Superlite Dragon

I then did some test flights. But a new problem was emerging:  my airspeed indication was failing completely at the extremely high angles of attack which I was testing.


In looking at the pitot tube, I suspected that the air intake on the pitot tube was 'micro-stalling', due to the non-parallel flow of air hitting the pitot tube obliquely at the high angles of attack.  In other words, the pitot tube needed to match the flow of air, not be parallel to the bottom of the wing.  I mentioned this to Gene, and he simply grabbed the pitot tube and started to bend it down.


"If you do this slowly, you can do it without breaking the tube," he said.  Hmm.  He was right.  


After he bent it a little, I bent it a little more.  The pitot tube was now bent distinctly downwards.

pitot tube bent downward on ultralight aircraft, EG Belite Superlite Dragon

I then performed another test flight in the plane.  After placing the airplane into a minimum controllable airspeed, I captured the following pic:

A picture showing a high angle of attack on a Belite

The above picture nicely illustrates the very high angle of attack.  Due to the fact that the engine is throttled back, it is safe to assume that the actual angle of attack is higher than what is illustrated:  the airplane is descending!  

As I maintained this very low airspeed, I focused my attention on the instrument panel, and captured another picture of the flight condition:

Cockpit panel view during Vortex Generator Stall Test

The instruments are a little hard to read in the photo above, so I've enlarged that part of the pic:

Closeup of instruments

The altimeter is reading 700 feet; the air speed indicator is reading 30mph, the RPM is showing 4700, and I was able to sustain this low flight mode without stalling the airplane.


The 30mph LED is actually a speed range indication:  the actual indicated speed of the aircraft is somewhere between 28 and 32.5 mph.  This is subject to several different errors, such as pitot installation error (EG, the pitot is not located far enough forward of the leading edge; or it is not parallel to the flow of air....), instrument design / calibration error (I try and make a good instrument, but it's not perfect....), etc.  


And if I pulled the nose back just a smidge more, the airplane stalled.  I was able to get the 28mph LED to flicker on a time or two as the plane progressed through the stall.


The aircraft weight, as tested, was around 522 pounds including airframe, parachute, pilot, and fuel.  This is substantially higher than the FAA mandated testing weight --  I would need to lose considerable weight to get down to the mythical FAA weight of 170 pounds. 


TECHNICAL MATH STUFF STARTS HERE...  

Let's do the math for predicting our stalling speed, and then compare it with what the LED Air Speed Indicator was telling me:


Using the textbook calculations for stall speed, which I first mentioned several months ago:


Vs=SQRT(2*Weight/(Rho*Area*Cl))

Where the following variables apply (using English units of measurement):

Weight = Weight in Pounds of the loaded flying airplane = 522 pounds
Rho = Density of Air  = .00237 slugs / ft3 (Temperature = 59 degrees, at sea level.)
Area = Wing Planform Area in SF = 101 Square Feet for this test
Cl = Coefficient of Lift = estimated at 2.4

So our equation now looks like this:

SQRT (2*(522) / (.00237*101*2.4)) = 42.63 ft/sec = 29.1 mph predicted stalling speed (at a weight of 522 pounds)


and this agrees with my observation -- the stall speed was above 28mph.


Now let's change the weight to a mythical amount of 478 pounds.  (278 pound airplane with chute and goodies, 170 pound pilot, 30 pounds of fuel).


and let's rerun the math with this new hypothetical weight:


SQRT (2*(478) / (.00237*101*2.4)) = 40.8 ft/sec = 27.8 mph predicted stalling speed (at a weight of 522 pounds) (The FAR Part 103 requirement is 28.0 mph.)


END OF TECHNICAL MATH STUFF -- YOU CAN BREATH A SIGH OF RELIEF


Earl Downs told me anecdotally a few weeks ago that the original Kitfox Lite was designed to barely meet the stall speed requirement of FAR Part 103.  Since our wing is the same aerodynamics, we've matched that characteristic.  And we keep finding that the math (and the actual results) point to a stall speed which is right at or under 28 mph.

This all makes sense -- the highest possible stall speed would also correlate to higher cruise speeds with the least amount of horsepower.  In other words, you can touch both ends of the FAR Part 103 ultralight aircraft flight envelope with a Belite - from 28mph stall to 62mph cruise.

Now some thought kickers for you to consider:

1)  These results were tested at fairly high density altitudes.  What would lower altitudes and temperatures do to the results?

2)  Does FAR Part 103 care that the stall speed is higher as the cabin load is increased?  

3)  What effect, if any did the vortex generators due to the stall speed?

4)  Is it fun to fly around with the airspeed indicator showing just 30mph?  [Answer is YES!]

a Hayfield Landing Highlights Belite's Utility

Long time readers of this blog may be aware that I have had training in mountain flying.  I've been to Idaho many times, and I've enjoyed the skills I've acquired through mountain flying school and through practice into short, odd airfields.  A recent post on this subject concerned several camping trips into the Thomas Creek airstrip.  Another post covered, among other thing, a series wasp bites and and description of the gnarly final approach into the Shearer airstrip, deep in the Selway-Bitterroot wilderness in Idaho.

I enjoy flying into tight, short airfields that curve, hug terrain, pass by trees, and slope uphill.  Ideally, they end in the side of the hill (and offer good camping and fishing nearby).

There is a hayfield next to our primary runway that offers some of these characteristics.  It slopes uphill.  It has a nice collection of trees.  It has bumps.  It has quite a bit of grass and weeds.  It is relatively short.  It is 'unimproved'. 

It is an ideal location for showing the landing capabilities and utility of our airplane.  The rough ground is a great demonstrator for our spring landing gear.

I wanted to demonstrate a nice 3 point landing, uphill, through the hayfield.  I asked my able assistant Gene Stratton to standby and take pictures.  I promised him a series of approaches into landing.  As I 'dialed in' the strip, I was able to establish a final approach of just a few feet over the weeds at the beginning of the field.  (Good mountain flying technique suggests the ability to hit a 50 foot spot... every time.  You can do that with a Belite.)

The photos show the story.

Hayfield Short Final, over the weeds.  I love this picture.

Over the 'numbers', field slopes uphill from here.  Another great pic.

Wheels kiss down on the Hay

Another approach, a little higher

Rollout in the hay, uphill.

Engine shutdown after taxi back

I'm posing by the Superlite

Belite Superlite poses in the grass, by the trees.  Where's the trout stream?

 This flight occured on September 28, about 1:30 in the afternoon.  I tracked down final, adjusting for the crosswind.  (Gene and I talked about my final approach crab angle after we debriefed on the ground, post-flight.)  Winds were out of the north, 12 knots gusting to 19 knots.  Engine power was set at about 35HP, even though the big Hirth develops 50HP when it's fully unleashed.  Landing direction was ENE; about a 50 degree crosswind.  FWIW, Wichita (KICT) Metar weather was:

       KICT 281753Z 01012G19KT 10SM SCT044 
            SCT150 SCT250 24/13 A2998

If you are a potential purchaser, you might compare our Belite with other less capable ultralight aircraft that have stiff gear and no crosswind capabilities and no off-field capabilities and no ChromAloy steel in their structure -- in other words, ultralight aircraft that lack safety, strength, and fun.

A Belite exudes utility and usefulness, and is a blast to fly.

      --  Photo credits: Gene Stratton.

Belite Fuel Gauge Installation

Our Belite Electronics are keeping me running, just catching up with orders.  (And no, we're not caught up with orders.  Not yet, anyway....)

One of the more popular products is the Belite Fuel Gauge.

Types of Belite Fuel Gauges

It's available in a version compatible with standard 2.25 inch instrument cutouts ($74.95):

Fuel Gauge from Belite with 2.25 inch round bezel

 It's available in an ultralight version with dimensions of 1.75 x 1.75 inches (and a weight of about 15 grams) ($69.95):

Fuel Gauge from Belite with 1.75 inch square bezel

The electronic design of each of these products is identical; the only difference is the bezel size and dimension.  They are designed to attach to a "capacitive fuel gauge", which is available from us and from several other vendors in varying lengths.  (No secret here:  we use one manufactured by Falcon Gauge.)  Here's what a "capacitive fuel gauge" looks like ($99.95):

Capacitive Fuel Probe, 12 inch length.

The probe has no moving parts whatsoever.  It senses the fuel level by the electronic effect of increasing or decreasing capacitance.  But, as they say in the movies, that's not important now.  The only thing you need to understand is that the probe outputs a voltage level that exactly correlates with fuel level in the fuel tank.  The voltage varies between 0 volts (empty tank) and 5 volts (full tank.)

Installing the Fuel Gauge and Fuel Probe in your airplane

Hooking these things together is not difficult!  Basically, this is what you need to do:

1)  Install the Fuel Gauge in the panel.  2 screws and a hole in your panel gets this done.

2)  Install the Fuel Probe in your tank.  The one we sell is 12 inches long, it may be put at an angle inside the tank.  Different probe lengths are available from Aircraft Spruce.  Some are bendable.  (You bend them only where they enter the tank, the remainder of the probe goes through the tank at a diagonal.)  Here's a photo of a fuel probe, installed in a tank with a depth of 8".  The capacitive probe was bent and fitted through a hole in the top of the tank, then attached to a small block of wood and bonded to the tank with a fuel proof expoxy.

Capacitive Fuel Probe installed in tank

3)  Attach our Fuel Gauge to a source of power.  A 9 volt battery works great; as does regular +12 volt system power.  (+12 volts is probably a better choice, because the separate fuel probe requires +12 volts).  This power goes to the power connector on the back of our unit.  Attach the ground as well.

4)  Attach the Capactive Fuel Probe to a source of power.    +12 volts works just fine.  This goes to the red wire, attach the black wire to ground.

5)  Attach the Fuel probe sender level wire (yellow color) to our Fuel gauge connector (usually this wire is marked with "FG" or something like that; it's the middle position on the fuel gauge connector).  (Yes, you'll have to run some wire from your fuel tank to your fuel gauge.)

6)  These two units also need a common ground.  This just means that the ground from the Fuel Gauge must be common to the ground at the Fuel Probe.  This is usually done through the metal frame of the airplane, but can also be done by a good ground wire as well.

At this point, if you turn everything on, you'll show the amount of fuel in your tank.  Well, not exactly; because it hasn't been calibrated yet.

Calibrating the Belite Fuel Gauge.

USE CARE AND CAUTION WHEN HANDLING GAS!!!!!

1)  Make sure the end of the fuel probe is about 1/4 or 1/2 inch above the bottom of your fuel tank. 

2)  When the fuel tank is empty, adjust the 'empty' trimmer on the fuel probe so that the only LED illuminated on the fuel gauge is the 0% (EMPTY) indication.  Be careful, it may be a very slight adjustment.

3)  When the fuel tank is full, adjust 'full' trimmer on the fuel probe so that the 100% LED (FULL) is illuminated.  Be careful, try and adjust so that the 100% LED is barely enabled.

4)  Empty the gas tank and verify the LED indications as the tank empties.  Readjust trimmers as necessary.

5)  Use common sense when flying with your new Belite gas gauge.  Assume that your gas gauge is inoperative if it does not agree with your normal pilotage fuel consumption calculations.

Fuel Gauge FAQ's

1)  Will the Belite Fuel Gauge work with anyone's fuel probe?  A:  It will work with any fuel probe that outputs 0 to 5 volts.

2)  What happens when the gas is below the bottom of the fuel probe?  A:  If properly calibrated, the Fuel Gauge will show 0%; your engine will continue to run as long as you have usable fuel in the tank.

3)  How are the markings on the Fuel Gauge designed to work?  A:  When the Fuel Gauge indicates 50% remaining, that means that the tank has at least 50% of the fuel capacity remaining.  When the the 50% LED  goes out, and the 40% LED turns on, this means you have between 40 and 49% of your fuel remaining.

4)  Are the readings accurate?  A:  If properly installed and calibrated in a square tank, they are reasonably accurate.  However, you must test your readings using a real fuel consumption test, with dip level verification of the tank readings.

5)  Are the readings accurate in a round tank (such as Belite's spun aluminum fuel tank, placed on its side)?  A:  They are reasonably accurate at the full, 60%, 50%, and 40%, and at empty.  Due to the circular tank, the fuel reading is not linear.  However, it's still completely useful information, because it can be used to compare fuel burn and gain judgement to fuel exhaustion from flight to flight.

6)  How much power does the Belite Fuel Gauge use?  A:  About 20ma.  It will run off of 8 AA (== +12 volts) batteries for approximately 100 hours!!!!  (Not counting battery current drain of Fuel Probe.)

7)  What is the labeling on the face of the Belite Fuel Gauge made from?  A: It's made from a waterproof membrane.  It doesn't shrink or wrinkle in humidity.  (This is a recent change to our production.)

8)  My Fuel Gauge has four wires going to the connector?!  What's the fourth wire for?  A:  Two wires are power (ground and +12v); one wire goes to the fuel probe, and the fourth wire is a dimmer input to the LEDs.  Leave it UNCONNECTED and you will have full brightness.  Connect to +12V, and the LED display will dim.

Have any more Fuel Gauge questions?  Give us a call or send us an email, info@beliteaircraft.com

-- James

Kitplanes Magazine Comes and Visits...

We were pleased to have Ed Wischmeyer with Kitplanes magazine pay us a visit today!

I had a great time showing Ed our airplane and our shop.  We'll see what he has to say in a few months.

Pictured below is Ed, after he completed a test flight in the Belite Superlite.

Ed Wischmeyer of Kitplanes magazine concludes a test flight and makes some notes.

James Takes Entrepreneur Test

The results are scary.  See for yourself.

James Takes Entrepreneur Test

Thunderbirds, Kathy and James, and Pres Huston

A mix of thoughts:

The USAF Thunderbirds are performing in Wichita this weekend. 

One of the benefits of owning an aircraft company in Wichita, KS is receiving an invitation to a reception in honor of the Thunderbirds, at McConnell AFB.  (I say this with a hint of humor -- with four full time employees, [including myself, Kathy] we are not (yet) deserving of such an invitation, but we are very appreciative.)

The reception had some great food.  Before the jazz band started playing, we were privileged to hear from 3 WWII veterans.  The first of these three men was Loren Corliss, and he told a gripping story of parachuting out of a destroyed B26, then surviving and moving through the jungle, towards eventual rescue many days later.  This man's story was originally told and printed in our hometown Wichita Eagle, in an article which you can read here.

Loren's rescuer was a PBY Catalina pilot, who landed in hard surf, and yanked Loren Corliss and several others out of war's grip to safety.  Loren Corliss never knew or got to thank his rescuer, until the story ran in the Eagle, and his rescuer read the story -- and discovered who he had rescued.

The rescuer was Harold Strub.  Harold was our second speaker last night.  His story of landing in extraordinarily difficult conditions was amazing.  You can read his story here.

The first person account of both these veterans held the entire crowd in awe.

A third WWII veteran also spoke;  I'm sorry that I don't have his name.  He had bailed out of another plane over Italy during the war; badly burned, and losing both hands, he still survived.  Another gripping story.

I thought of my father-in-law, Pres Huston.  Now deceased several years ago, I was reminded of his participation in WWII; how he fought, how his voice would now sound older and more grizzled were he still alive.  How he would also have stories to tell.  How he was a peer of our aging WWII veterans, with just a few still living.

After the aging veterans had said their pieces, the USAF Thunderbird lead pilot made comments of these aged veterans:  echoing comments made by other writers, "these were our greatest generation".

I thought again of Pres Huston. 

My wife, Kathy, was standing in front of me.  I gently stroked her shoulder, as we listened to the speakers, as I thought of Dad.

The evening ended; the huge Thunderbird group left; the band continued to play.

USAF Thunder Bird Lead Solo Rick Goodman, with Kathy and James

Flying the Belite Ultalight Aircraft - Part 3

This is the third of three parts.

Approach and Landing

Flying an airplane is one of life's second most exciting experiences.  And, of course, the first most exciting experience is landing an airplane.

Fortunately, the Belite keeps the excitement level to a minimum.  It lands in a manner very typical of any tail wheel airplane.  A full stall landing, that is, touching down on the main wheels and the tail wheel simultaneously, is the best method to use and results in a low landing speed.  Given even a modest headwind, your actual touch down speed may be matched by someone jogging down the runway.  Due to the very light weight of the Belite, the airplane will decelerate rapidly after landing, especially if you make use of the brakes.  The rudder will remain active until you are almost stopped.  The heel brakes help with directional control; keep the airplane tracking straight.

Pre plan your traffic pattern.  Ultralight aircraft will often fly a lower, close-in pattern.  It may be on the opposite side of the airport pattern.  Seek council of other experienced local pilots.  Check with the airport manager.  Be vigilant.  Be prepared to give way to other aircraft, even if you have the right of way.  Be especially watchful for wake turbulence.  Fortunately, the Belite has excellent control authority.

Typically your approach begins when you are on the downwind leg, opposite your touch down point.  Reduce power to the point that your descent matches any other light aircraft.  Don't reduce power to idle, the descent will be very steep.  (This can be done later, after you have appropriate experience and know your altitudes and airspeeds and descent paths.)  As your turn base, use 1 notch of flaps and slow to about 50mph.  Select a second notch after turning final, and adjust power to hit your touchdown point.  Keep your airspeed at or above 45mph.  Add power if you are low.  Add a third notch of flaps when on short final, after the numbers are assured.  Don't pull back on the stick to stretch a glide -- the aircraft will stall.  Use power instead.

When you are over your landing point, at an altitude of 3 to 5 feet, level the plane off and reduce the remaining power.  The Belite will settle towards the ground and decelerate.  Just prior to touch down, pull the stick back to full flaw and touch down on all 3 wheels.  (The Trike works the same way - pull back and let the plane settle on the two mains, try and make the tail 'kiss' the ground.  Keep the stick back, whether in the Trike or the taildragger.) 

If you want to be more conservative, and have the runway available, keep a little power throughout the flare.  Reduce the power after touchdown. 

The approach and landing can be made from a power off glide, but the descent angle will be very, very steep.  By maintaining 45+mph (which you can do just by pushing the stick forward and the nose down) you will have plenty of energy for the flare.  You can use a shot of power to clear obstacles.  As a note of interest, the high angle of descent cause by idle power is caused by the windmilling propeller drag, not by the airframe.  If you stop the prop, the Belite is a fine little glider, with an estimated glide ratio of 9+ to 1.  Of course, a stopped prop is disquieting.  Or perhaps, very quieting.

The use of approach speeds that are slower than 45 MPH is possible, but not recommended.

Emergency Procedures


As with all aircraft, you should be prepared for emergency situations.  Preparation is key -- starting with your preflight.  Are both mags working?  Has the safety pin been removed from the parachute?  Are the wing bolts latched properly?  Are the flapersons properly connected?  Has the fabric been torn?  Is a wasp living in the wing spar?  Is the pitot plugged?  Are the tires properly inflated?  Are the bolts tight?  Are the winds acceptable?  Are you prepared for the flight?  Is the runup of the engine normal?  What is the forecast?  Will the winds turn?  Does the flight have continuous emergency landing options?  Does anyone know where you are going, and when you will return? These are just a few of the things on your checklist.  

It is hard to separate good planning and caution from safety.

The Belite is available with or without electric start.  If your engine quits, and you are unable to restart in flight, you will soon experience and unscheduled landing.  First of all, you must fly the airplane.  Lower the nose, maintain 45 to 50mph, and fly the airplane.  Did I say, fly the airplane?  The surprise of an engine stoppage causes some to forget to fly the airplane, which usually begins with a pitch forward (on the control stick) in order to maintain flying speed of 45+mph.  

With the prop stopped, your glide ratio will be improve.  From an altitude of 500 feet, you have a landing radius of up to a mile in any direction.  Don't overshoot the landing.  Use flaps as required.  Use S turns as required.  


The Belite carries a 5 gallon fuel supply, so be mindful of your available fuel.  Given the approximate 1:20 to 2:00 fuel supply, you have plenty of fuel for fun, but must be extremely careful when planning cross country flights, especially with headwinds.  A precautionary landing with the engine running (and I've done it) is a far safer option than letting a dead engine make the decision for you.  Carry water, a cell phone, and perhaps, a personal locator, such as Spot.  (And carry oil, for refueling at remote airports.)


Develop your flying skills.  The Belite is truly a very high performance airplane -- it is capable of more responsiveness than almost all other FAR Part 103 ultralights.  It is also capable of far more utility.  Use your developed skills to improve safety.  Fly within your personal limits provides the most fun with the least risk.


Enjoy your Belite!

Flying the Belite Ultalight Aircraft - Part 2

Editor's note - this is Part 2 of our series on how to fly a Belite Ultralight Aircraft.  

Climb

With the horizontal stabilizer trim set properly, the Belite will have a fairly neutral stick feel during climb.  (If it doesn't, continue to fly the airplane, and trim the airplane after landing (or during cruise, if equipped with electric trim).  As previously mentioned, a climb speed of 45 to 50 mph works well.   Your rate of climb is dependent on many factors:  weight, temperature, engine power, propeller pitch, etc., but will vary between 100 to 1000 fpm.  In a brisk wind, the climb angle can seem quite dramatic.   In fact, with a little headwind, an absolute altitude gain of 800 feet over a ground distance of 1/2 mile is achievable!

You will notice that the ailerons are light and responsive and the rudder coordination will be needed to offset P factor and adverse yaw.  While the yaw effect caused by ailerons is not pronounced, application of the rudder in the same direction of the flaperons will result in nicely coordinated turns.  (This becomes automatic after some flight time is accumulated.)

Belite's slip-skid indicator can help with rudder coordination, but I've learned to fly the aircraft with absolutely no instruments installed -- you can too, if you want. 

The Belite ultralight aircraft is highly sensitive to angle of climb -- the plane will quickly slow down (and stall) if pulled up; conversely, a nose down attitude will result in a rapid airspeed increase and stall recovery.  As you gain experience, you will wish to experiment with pitch control to get a better idea as to how the Belite relates to pitch versus airspeed changes. 

By the time you are one hundred feet off the ground, you may notice that your aircraft has no doors.  Even so, there is very little airflow in the cabin area and there is no sense of buffeting by air moving past the 'no doors'.  Do not let the 'no door syndrome' distract you from flying your new ultralight airplane.

On your first flight, climb to a safe altitude and stay in the pattern.  You may wish to circle the pattern several times before landing the Belite.

But before landing let's consider some flying basics.

Level Flight and Flight Maneuvers

Level flight can be determined by checking your altimeter and VSI, like any conventional aircraft, and adjusting stick and power to neutralize climb.  Your indicated airspeed will settle in at 55mph (with a 28HP engine) to 62mph (with a 38HP engine) to 70+mph (with a 50HP engine, in experimental configuration).   With the horizontal stabilizer properly trimmed, the control stick should have a neutral feel.  Small pitch and power changes can be made to maintain level flight.  A low horsepower engine will lose RPM and power quickly when the nose is raised.  Conversely, it will gain RPM when the nose is lowered.  Don't chase level flight -- trim your aircraft properly (either on the ground, with a fixed elevator tab, or in the air, with electric trim).  Then set the power and let the airplane settle down, like any other airplane.

Turns in the Belite ultralight aircraft are made in the same manner as previously described in the 'climb' section.  Remember to practice great rudder / aileron coordination.  The rudder needs to be moved only when moving the ailerons.  Once a turn is started, the airplane will continue to turn even if the controls are neutralized.  Consequently, turns are stopped by applying a small amount of force in the opposite direction.  Practice safety when turning:  the excellent visibility of the Belite allows the pilot to look right, left, and backwards before a turn is started.  You should even look overhead, which is easily done through the clear top windshield.  This also allows you to see into a turn, as it is begun.

Always observe safe airspeeds:  maintain Vx or higher (45 mph) in climb or slow flight, unless practicing stalls.  The airplane will stall at approximately 28mph indicated airspeed, at sea level, when loaded with a 170 pound pilot, with full flaps, under standard atmospheric conditions.   The airplane will stall at 34mph indicated airspeed, at sea level, when no flaps are selected.

Do not exceed 65mph, except in smooth air.  Never exceed 80mph under any circumstances, it is the red line (Vne) of the airplane. 

Once you are comfortable in level flight and turns, begin to practice flying at speeds that are less than normal cruise.  Reduce power slightly and slow the plane to 45mph; this is a good to practice slow flight at.  You will be able to maintain level flight at this power settings, although it may require some work. 

If you add one notch of flaps, you'll notice that the nose of the airplane will immediately pitch down, but just slightly.  You'll need to add some power to maintain level flight.  With two notches of flaps, even more power will be necessary to maintain level flight.  The last notch of flaps adds considerable drag, plus even more power.  We don't recommend using this last notch of flaps, as it requires considerable power and slows the plane down rapidly, requiring a very steep approach angle when power is reduced.

For a normal approach, reduce power to about 65% and dial in one notch of flaps.  This will place you in a normal approach configuration, with a normal approach path.  Practice turns in this configuration.  Also practice go-arounds by adding full power, slowly retracting flaps and establishing a normal climb.  Learning how to go-around is important, as it gives you a safe plan should you reject a landing for any reason.

Stalls must also be practiced in the Belite, but they are predictable and gentle.  Be sure to practice stalls at least 1000 feet above the ground.  Start stalls with no flaps; reduce power to flight idle and set up a 45mph glide.  Note the nose position; it will be low in order to maintain airspeed.  Slowly raise the nose and observe the speed bleed off - this will happen quickly.  There will be a slight shudder and the nose (and your seat) will drop as the stall occurs.  Immediately and smoothly, push the stick forward and the plane will instantly start flying again -- it's easy!  Then smoothly add power, and establish a proper climb.  Clean up the flaps, climb back to altitude, and practice some more.  Practice stalls with 0, 1, 2, and 3 notches of flaps, and with power off and with power on.  Note the low kinetic energy, especially with 3 notches of flaps.  In all cases of stall recovery, the nose must be lowered to the correct glide attitude as power is simultaneously applied.  If flaps have been used in the sall, retract them slowly, and transition back to a climb attitude.  Stall training is a great way to learn how the Belite is going to react during the flare to land.