Jan 19th

good news/ badnews

By monty stone

           doctor speaking to patient.  "well i have good news, and bad news"                                                                                                                                                          patient.."tell me the good news doc"                                                                                                                                                                                    doctor " the good news is you have thirty days to live"                                                                                                                                                                          patient.." doc, what's the bad news ?"                                                                                                                                                                                                             "the bad news is i should have told you three weeks ago"

Jan 19th

Brain teasers for those that believe down wind turns are

By Joe Hockman

If you believe that downwind turns are "different" from upwind turns, or if you think that a pilot can "feel" the direction of the wind, or that an aircraft tends to "weathervane" to point into the external, meteorological wind, then you might enjoy these brain teasers. Primary context is hang gliding but also applies to flying trikes.

Brain teaser #1:

1.) You are flying indoors.  In an immense, enclosed room.  The walls and floor and ceiling are black. You've launched off a platform near the ceiling and are practicing turns, stalls, stalls from turns, etc.  There is no evidence of any air movement in the room. Does your aircraft behave differently when flying in any particular direction?

2.)  Sunrise. You realize that what you thought were black walls, are clear glass panels. The room is actually the enclosed gondola of an enormous balloon.  As you look down at the newly visible earth, you see that the ground is passing by very swiftly far below. The balloon is in a stiff south wind, and is being blown northward over the land.  Now does your aircraft fly differently in any particular direction, within the closed room? Is it now more dangerous to turn downwind (toward the north) than upwind (toward the south)?  Just because the sun came up and now you can now see the ground? What if you close your eyes? Can you "feel" the wind by the way the aircraft responds when flying in different directions?

3.)  You notice that each of the transparent walls of this enormous, enclosed room has several large windows.  Someone comes and opens all these windows. But no air blows in through them.  Likewise the flags that decorate the outside of the gondola hang limp. Anyone who has ever been in a balloon will recognize this to be true, and the explanation for this is simple: the balloon is moving freely with the airmass without resistance, and so the balloon's velocity is constant, and so acceleration is zero, and so net force also must be zero: the wind cannot be "pushing" on the balloon in any way.  Since the windows are now open the airmass in the room is now the same as the airmass outside. Now does your aircraft fly differently in any particular direction? Is it more dangerous to turn downwind (to the north) than upwind (to the south)?

4.) The balloon is too heavy and needs to shed some weight.  Someone hits a button and all of the walls get jettisoned. The floor, ceiling, and corner pillars are all that is left of the "room".  Again, no air is blowing through the "room". Now is a downwind turn (to the north) somehow "different" than an upwind turn (toward the south)?

5.) You fly out of one of the missing walls and into the clear blue sky.  Now is a downwind turn any "different" than an upwind turn? Is it easier to stall when turning downwind than when turning upwind?

(P.S. Part 3 of brain teaser #1 brings to mind another old puzzle: if a fly takes wing within an enclosed aircraft, do the wings of the aircraft no longer need to support his weight?  What if a window in the cabin is open?  What if the fly is buzzing around the cockpit of an old open-cockpit biplane?  What if the fly flies out of the open window (or out over the side of the open cockpit) and then flies along in formation with the aircraft?  What if he positions himself directly over one of the wings?  At what point as the fly approached the window (if any) did the aircraft stop "feeling" the weight of the fly?)


Brain teaser #2:

We are flying in still air over the San Andreas fault. Suddenly the block on the west side of the fault starts sliding rapidly northward.  (Devastation is breaking out below).  As we fly from across the fault from east to west in the still, uniform, airmass, we suddenly find ourselves flying in a north wind in relation to the land immediately below.  Does this affect the way the aircraft flies?  When we are on the west side of the fault line, are we in more danger of stalling during a "downwind" turn (toward the north) than during an "upwind" turn (toward the south)? 


Brain teaser #3:

Aliens arrive.  After consulting with Art Bell, they decide to use their advanced engineering prowess to abruptly halt the earth's rotation.  You are piloting an airliner at 30,000' over the equator, and the effects of this little disturbance have not yet propagated to your altitude--the layer of the atmosphere surrounding your aircraft is still rotating at a normal rate.  From your perspective, the ground has suddenly started moving toward the west at 1,038 mph.  Relative to the ground, you are now flying in a 1,038 mph west wind.  Does this have any affect on the way that the plane flies?  Are "downwind" turns (toward the east) now different than "upwind" turns (toward the west)?


Brain teaser #4:

You are in still air. Looking straight down, you see a train driving south at 60 mph.  You decide that the train constitutes the "surface" of the earth for the few seconds that you are overflying it. As you overfly the train, you are in a 60mph south wind, in relation to the "surface".  Does this affect the way your aircraft flies?  If you close your eyes and fly in circles over the train, will the "feel" of the aircraft tell you which direction the wind is blowing, i.e. which direction the train is travelling?  Is there a greater danger of stalling when you are flying "downwind" (flying toward the north), or when you are performing a "downwind" turn (flying toward the north), than when you are flying "upwind" (flying toward the south), or when you are performing an "upwind" turn (turning toward the south)?

(Extra credit for hang glider pilots: do you have to "flare" your glider differently when landing on top of the southbound train with the nose of your glider pointing south, than when you land on top of the southbound train with your nose pointing north?  Obviously answer is "yes"--landing with a 60mph tailwind would be disastrous--but why?  Does it have to do with the behavior of your glider in relation to the air?  Or does it only relate to the fact that you are trying to minimize your glider's groundspeed at the instant that your feet touch the ground?  If you were practicing flares at high altitude, aiming for a given profile in the airspeed and sink rate with no concern for ground track and groundspeed, could you tell when you were over the train by the way the glider felt when it flared?)


Brain teaser #5:

This one also applies to those who believe that an aircraft flies differently in "lift" (rising air) than in "sink" (descending air).

Let's ignore the earth's surface, and take the sun as our reference point. In relation to the sun, the earth's atmosphere (as well as the rest of the earth) is moving at 66,674 mph.  If we are near the equator, the direction of motion of the atmosphere (as well as the rest of the earth) is (roughly speaking) toward the west at noon, toward the east at midnight, straight up at sunrise, and straight down at sunset. So we have an east wind at noon, a west wind at midnight, an updraft at sunrise, and a downdraft at sunset.  (Don't confuse yourself by factoring in the earth's rotation around its axis, which is a mere 1,038 mph at the equator).  Bearing this incredible wind velocity in mind, does an aircraft fly differently when turning to the west at noon, then when turning to the west at midnight? Does an aircraft fly differently in the sunrise updraft than in the sunset downdraft?

Jan 18th

Motorkite Dreaming (Cool Video Link)

By Rizwan Bukhari

Hi All,


Here is a cool link for you to enjoy some trike flying fun video. I own the Motorkite Dreaming dvd (which is different than this, some parts are the same). Fun video for all trike pilots :D


I hope you enjoy it





Jan 16th

Sun N Fun or Oshkosh or just the Flyins?

By Rizwan Bukhari

Hi all,


I live in Boise, ID and have never been to Sun N Fun or Oshkosh and was wondering for someone who has prime interest in Sports/Recreational flying which event (Sun N Fun or Oshkosh) is better.


I might visit one of these events this year and was wondering if anyone could give me some tips about their experience to either of the events and what did they like, what were some of the challenges of either of the event.


Or, is it just better to attend the local flyins?





Jan 15th

Thoughts on safety.

By Bryan Tuffnell

Why are so many trike pilots dying? We've heard lots of answers to that, most of which I don't buy. God isn't lurking behind a cloud with a Lee Browning taking potshots at unlicensed pilots; if engine failures had to be fatal there wouldn't be a whole lot of hang gliding going on; if higher performing trikes were dangerous how come so many of us are clocking thousands of hours in them?

The root cause of the majority of triking accidents is surely that the pilot lost control of the aircraft, for whatever reason. And yet trikes must be about the easiest aircraft to control. What's going on?

I don't see many stall related accidents; nor is tumbling much of a feature. You've got to be trying to get into trouble through pure pitch. Trike pilots have little direct, independent control of yaw. Trikes don't spin. I'll bet dollars to donuts that most accidents happen because either the pilot can't roll fast enough, or far more commonly, because they can't remove bank - they are locked out of a turn.

This is topical, with all the discussion about roll that's been happening. It's also a pet subject of mine (hold me down).

Every three axis and rotary wing pilot knows how to coordinate a turn. Every trike pilot should know to pull in to initiate a change of bank, and to push out to turn a roll into a constant rate turn. Yet I believe that this lack of what should be a fundamental skill is killing pilots.

This is where the fuss about spiral dives and slipped turns and Arrow wings come from. What's the solution? I see three possibilities:

1 Manufacturers dumb down wings to cater for inadequate skills.

2 An upping of the standard of instruction, somehow.

3 A rating system for matching pilots with trikes.

Higher performing trikes are not harder to fly. There aren't killer wings. There are some trikes that ask their pilots to have a basic comprehension of the roles of pitch and throttle in banked flight, nothing more. I think having instruction that includes Turns 101 could save lives, and is the answer. I don't know how to make that happen.


What do you good folks think?

Jan 8th

How a trike rolls presented with a totally new perspective 2

By Paul Hamilton



This presents a completely different mindset  to look  at the trike rolling into a turn.  It was presented by RB so I will do my best to convey the message/concept. Historically, we have been looking at shifting the weight under the trike wing creating the turn. Forget all that for a minute and open your mind to a different perspective, a new way of thinking about how a trike rolls into a turn.  Simple. We are not shifting our weight under the wing to roll it, WE ARE  TILTING THE WING ABOVE THE TRIKE carriage which starts the turn.




This can be easily seen in this video. Note that the bar is moved, the wing tilts above the trike undercarriage the trike under carriage (with the camera attached) initially do not move much. Then after the wing tilts you can see the trike undercarriage/camera get into the turn AFTER the wing is tilted.  You can see this most clearly flying straight going into a steep turn and also coming out of  a steep turn. This can be clearly seen in this video.







Look at the simple physics. As an example: you have a 1000 pound trike undercarriage and a 100 pound wing. You have 1000 pounds verses 100 pounds, TEN TIMES the mass trying to oppose each other. Which one is going to move more, simple: the lighter weight wing. Yes it could be 5 to 10 times based on the specific weights but we will use 10 here to make the math simple.




So with 10 times the difference in mass, basic physics provides us an easy way to quantify this. You tilt the wing 40 degrees and the undercarriage moves 4 degrees.  Exactly as shown in the video.




So we rotate the wing, the lift vector goes to the side so we start turning. Hopefully we all remember this horizontal component of lift. The problem is that our momentum 1100 pounds at 70 MPH (or what ever speed/weight) wants to keeps us going straight based on Newton's First Law of motion.




So now we have a trike initially being pulled to the side from the changed lift vector, turning but pointed straight. Kind of a mess to start. It appears we are flying sideways to the relative wind. That pesky sideways adverse yaw we know happens but debate exactly how.  Well over time, however many fraction or seconds it takes, the trike yaw stabilizer (nose angle/billow/wheel spats/tip rudders or what ever you want to call it), the trike stabilizes in yaw track the trike into the turn. That pesky adverse yaw goes away. At about the same time (before, during or after which can be debated) the undercarriage swings out from the centrifugal force and we are in a coordinated turn.




Make no mistake, we are shifting our weight, changing our CG under the wing which helps roll the aircraft, but start thinking of it in a new way/perspective and perhaps it will make more sense.


 You can see from the video clearly that for a trike the wing tilts more than the carriage moves to start the turn.




I know all this perspective is very hard for anyone to swallow after we have been taught what we are shifting our weight to initiate a turn. Yes, again, this weight shift is correct but based on physics we are tilting the wing MORE than shifting our weight under the wing to turn it.




How are hang glider turning dynamics fundamentally different from the Trike? Weight ratio.




Look at the hang glider 70 pounds and the pilot at 170 pounds. Only two and a half difference verses 10 for a trike. So the pilot verses wing ratio is significantly different tilting the wing less and bringing the pilot underneath the wing more. Should we continue to base all our highest levels or roll based on a different animal?




Why is everyone's perspective of the weight shift trike turn initiation, weight shift rather than tilting the wing? We have all been brainwashed from the hang glider designers from day one. I am totally guilty of this myself. It started as we were infant pilots and grew. It goes to the fundamental principles of learning for humans: Primacy- we learned it first creating a strong almost unshakable impression, Readiness - we want to learn to challenge and keep us safe, Exercise - it has been repeated so much it is continually reinforced, Intensity - we practice it and imagine it during flight plus we are passionate and emotional about it as we debate it.




With all these fundamental principles of learning engrained it will be hard for many to embrace this new concept.



There you have a completely new perspective of looking at roll for the trike. We have a long way to go to develop, understand and evolve our sport so perhaps this new perspective will be helpful.


Jan 2nd

Firesleeve or No Firesleeve, that is the question

By Rizwan Bukhari

Hi all,


I was reading up on Rotax 912 engines and realized that same 912s come with Firesleeve and  some without Firesleeve. Which got me thinking why some engines on trikes have Firesleeves and some do NOT? Is this a manufacturer's discretion and some order engines with Firesleeves installed and some without it? and is this an important safety concern?


Following is the picture of an engine with firesleeve on it's fuel lines. (The firesleeve is orange in color in this picture).


My limited understading is that the purpose of firesleeve is to sustain an engine fire for 5- 15 minutes. Hopefully enough time for you to take necessary steps for your safety.


Now my question is

1) Howcome in the above picture, there is no firesleeve on the fuel lines running to the carbs? Are there only few critical areas where a firesleeve is needed?

2) Howcome some trike engines come with them and some don't?

3) Are they important safety item for trike pilots?

4) And the most important question is that can a Firesleeve prevent a Fuel Line Vapor Lock? Or does the Firesleeve NOT play any role in preventing a Fuel Line Vapor Lock?


Thanks for your help.









Jan 2nd

Twist and Washout in the Trike Pilots Handbook and Why Billow was replaced

By Paul Hamilton




When the FAA Weight Shift Control Aircraft Flying Handbook was being written, one of the objectives was to standardize the terminology so that the WSC trike could most easily be understood by existing and new pilots.




The term billow was initially used by hang glider manufacturers with the original Rogollo wings to add material so the wing was not flat. The nose angle was 90 degrees and the sail was designed to be 95 degrees. At this time this was considered billow so the term "billow" has hung on over the years.




In fact with my hang glider design background,  I personally used this term in the manual along with wing "twist" and "decreasing angle of attack" towards the tips. My FAA review team asked "what is this billow term?. We do not see it in any credible aerodynamic description". The dictionary term was interesting and did not look like any thing related to sail design:






[bil-oh] /ˈbɪl oʊ/




1. a great wave or surge of the sea.


2. any surging mass:


billows of smoke.


verb (used without object)


3. to rise or roll in or like billows; surge.


4. to swell out, puff up, etc., as by the action of wind:


flags billowing in the breeze.


verb (used with object)


5. to make rise, surge, swell, or the like:


A sudden wind billowed the tent alarmingly.




It was explained that all these ancient "Tribal" terms from old times/technology needed to be updated/modernized to commonly known aerodynamic principles. I was initially perturbed/irritated with this but I moved on.




rIt was also brought to my attention that the current FAA reference 2005 for trikes (Lucian/Hal Trikes- Flex Wing Flyers) Page 3-29 Flex Wing Flyersdoes not have the term "billow" anywhere. It uses the common aerodynamic terms "Twist" and "Washout" as the concept was introduced. Again on page 3-39 Flex Wing Flyers the word twist and washout were used to describe turning. No reference or term "Billow" anywhere in the book or  anywhere in any credible aerodynamic resource i could find with an exhaustive search.




I was convinced/forced to comply that both "Twist" and "Washout" were credible aerodynamic terms and we did not need to invent billow to confuse the issue.




So I added in the Aerodynamics section page 2-3 the common aerodynamic terms twist and washout and addressed the term billow to transition everyone over to the established aerodynamic terms on page 2-3:




Wing twist is the decrease in chord angle from the root


to the tip chord, common to all WSC wings and ranging


from 5° to 15°. This wing twist is also called washout as


the wing decreases its angle of attack from root to tip. The


term billow was originally used for the early Rogallo wings


as the additional material in degrees that was added to the


airframe to create the airfoil. It is still used today to define the


amount of twist or washout in the wing. The WSC may not


have twist/washout when sitting on the ground, and must be


flying and developing lift to display the proper aerodynamic


twist characteristic of WSC wings. [Figure 2-6]





Again on Page 2-13 twist and washout are described in turning on page 2-13:




Longitudinal Axis— Roll


Turning is initiated by rolling about the longitudinal axis, into


a bank similar to an airplane using aileron and rudder control.


To turn, shift the weight to the side in the direction of the turn,


increasing the weight on that side. This increases the twist on


that side while decreasing the twist on the other side, similar


to actuating the ailerons on an airplane. The increased twist


on the side with the increased weight reduces the AOA on the


tip, reducing the lift on that side and dropping the wing into a


bank. The other wing, away from which the weight has been


shifted, decreases twist. The AOA increases, increasing the


lift on that wing and thereby raising it.


Thus, shifting the weight to one side warps the wing (changes


the twist) to drop one wing and raise the other, rolling the


WSC aircraft about the longitudinal axis. [Figure 2-24] More


details on the controls that assist wing warping are covered


in chapter 3, which should be considered with use of the


controls in the takeoff, landing, and flight maneuvers sections


of this handbook.





Again on Page 3-9




Roll Control System


Control bar movement from side to side controls the roll about


the longitudinal axis. The wing attachment hang point allows


the carriage to roll around the wing keel. Thus, it can also be


looked at from the carriage point of view, when the control


bar is moved side to side, the wing rotates around the wing


keel relative to the carriage. [Figures 2-31 and 3-19]


It would fi rst appear that moving the control bar to one side,


thus shifting weight to the opposite side, could alone bank


the aircraft. It is true that shifting weight to the right would


naturally bank the aircraft to the right and put it into a right


hand turn. However, the weight alone is not enough to provide


adequate roll control for practical flight.


As weight is moved to one side, the keel is pulled closer to


that side’s leading edge. The actual keel movement is limited


to only 1 to 2 inches each side of center. However, this limited


keel movement is sufficient to warp the wing, changing the


twist side to side (as discussed earlier in the aerodynamics


section) to roll the aircraft [Figure 2-24] by changing the


lift side to side. Simply, the shifting of weight from side to


side pulls the keel toward the leading edge on that side and


warps the wing to roll the aircraft.


Besides the keel shifting relative to the leading edges and


crossbar, overall roll control is adjusted by the designers to


fit the mission of the wing through sail material/stiffness,


leading edge stiffness/flexibility, amount of twist, amount


of travel the keel is allowed, airfoil shape, and the planform


of the wing. [Figures 3-20 and 3-21]






So there we have it, why we used Twist and washout instead of billow and how the wing turns from the shift of washout and/or change in twist...






Dec 31st

I LOVE 'TECH', BUT........

By monty stone

i consider BALLISTIC RECOVERY SYSTEMS' technology level to be 'stuck' in the '1950' s auto era;  plate glass still used to look through, seat belts not used, or available, no crush zones, steel dashboards, rigid steering columns that ran from behind the front bumper to the chest ,minimalistic door catches that allowed doors to fly open going over a bump,remember 'suicide' doors that hinged at the back ? hoods that slammed back, to de-capitate front seat occupiers, air-bags only a dream of the future. remember 'hitlers revenge' the vw, 8gals of gas sitting on your lap, the vw bus had NO leg protection, a minor parking lot 'prang' resulting in MAJOR leg injuries, ford pinto with a gas filler pipe pushed into the gas tank through a rubber 'o'ring, and then mounted behind the rear 'bumper', in the 'rear end me here, position. (my own pinto had 'flammable' signs riveted all round it till a h/way patrol cop made me drill the rivets out and take 'em off! he probly was a shareholder!)  all these, and many other 'flaws' were fixed, finally, after much blood shed, and 'hand-wringing' of corporate 'penny-counters in the then to be , future.  well, the future  is HERE! the tech is available to take the human deployment out of the equation. it's just gotta be 'modified and adapted to fit the BRS. but, bussiness accumen of , if it costs more, it'll reduce our 'profit margin', and any way, we're selling all these the market can bear, will endure, unless enough pressure is bought to bear! so what if the price doubles from $5k to $10k, if it will STOP ME FROM 'DEADING' MYSELF, it's worth it!  my van has a 'knock' sensor that instantly senses a low octane gulp and retards the next few ignition sparks etc, to avoid damage, or inconvenience to the system. obviously, relying on the human to assess the threat, and  risk, decide and deploy 'AINT WORKING'! of all the trike tragedies that have occured in recent memory most, apparrently were equipped with 'the safety net' of an on-board recovery system, yet not one has saved the occupants. sure, if USED they possibly would have, but NOT relying on the human to deploy. yeah, i know that 'shxt' happens close to the ground, etc, but purchasers of these systems, for considerable $$ should have a better chance of success, than winning the lottery. if i were the 'high mucky-muck of one of these companies i would lock my chief designer in a cage, feed him on 'red meat' only until he comes out with a viable system to use TECH to overcome the human shortcomings of F.T.D. (failure to deploy). until then i'd replace that 'puny' little T handle with a 10 inch dia red 'panic' button mounted directly in front of the pilot's face hooked to a 'loud scream detector' wired to the deployment device as 'backup'. WHEN IS SOMEBODY GONNA WAKE UP? ..............................................................                                                                                                                         freazier nutszoff                                                                                                                                                                                 ps. hell! i might even buy one myself!                                  

Dec 22nd

Another great day, month and year for triking

By Paul Hamilton

We are going to have two trikes joining our fleet here in January.


The Delta Jet 2 is coming back. This is where we lost Ted to triking because his wife saw so much bad publicity providein the impression taht triking was dangerious and he sold his Delta Jet 2 to a student of mine who I have been training in the Revo.

We have the brand new Airborne M3-Sport coming for a student of mine who will eventually be opening a full time training Intro flight school in California.


Another great day, week, year for triking.


Happy holidays to all.