kasper Posted June 25, 2015 Posted June 25, 2015 Maybe you didn't understand my post; what you are referring to there is the CoG of the wing load, which, as we agree is fixed at the pivot point.The trike manual's statement probably should have said "aerofoil's balance, because it then goes on to include a fuel load calculator which is also what I referred to. If you think you can get away without filling out calculations based on that Fuel Load calculator, you're dreaming. I'll take the option of I'm dreaming thanks. The fuel load calc is nothing to do with W&B but simply WEIGHT. In a trike you are MTOW limited and the fuel load trade off is nothing to do with balance but pure weight. And given I consider that in relation to weightshift you are in deep hole and continue to dig I'll start filling in the hole - I do not agree that the pivot point is fixed, it is not. We have multiple hang points along the keel and they can, depending on the aircraft, be variable in flight - I even have an electric hang point moving set up on 1 wing so i can adjust in flight. In addition to the movement along the keel the likes of the Bionix wing have inflight variable geometry changing the sweep of the wing and as a result the effective position of the fixed hang point in relation to the aerodynamic centre of the wing! And just to be really pissy the entire P&M range of wings use combinations of camber change through luff line shortening for in flight trim (in addition to moving hang points) and/or electrically adjusting tension load trim on the keel ... again in addition the hang point. Them simple little hang gliders in trike are actually not simple at all 2 2
Guest Crezzi Posted June 25, 2015 Posted June 25, 2015 If you think you can get away without filling out calculations based on that Fuel Load calculator, you're dreaming. Filling out what ? The requirement is to operate IAW the POH e.g. 1 pilot (<= max weight) + full tanks + <= 70kg equipment = compliant with MTOW.
Guest Andys@coffs Posted June 25, 2015 Posted June 25, 2015 as someone who learnt under a HGFA instructor who now teaches under RAAus, I can say I was taught to manage weight not balance. I mean trikes in anything but perfect weather are things that need a lot of movement of the wing control bar, so in normal lumpy air the movement between, for example, full throttle and no throttle is relatively unnoticeable, similarly the difference between 1 up and 2 up from a bar perspective is also relatively unnoticeable. What is noticeable is extra drag... Someone in the backseat can swing either arm out palm forward, and the aircraft will start to slowly turn, unless control to counteract is fed in. But 2nd seat is behind pilot, and not far away horizontally from the hang point. If weight is added there, within limits, I suspect that other than the sluggishness wrt climb that every aircraft ever made has when additional weight is added would be the only affect..... If it was somehow something bulky but light and could somehow during flight move so that it creates asymmetric drag then that could be an issue....but an instructor getting caught by that wouldn't be my first semi educated guess....... Andy
Pearo Posted June 25, 2015 Posted June 25, 2015 True Pearo,I have been on bikes all my life, but not road bikes. I had the choice to buy a bike capable of 200 plus ks per hr with no instruction on how to ride it, or learn how to fly an aeroplane . I'm sure if I had tried hard enough I could get training in how to safely ride on a high powered bike. My point was that you don't get to fly any aircraft till you prove you have the skills to safely control and pilot it. With bikes all you need is 12 months on L plates and you can ride a Formula 1 road bike. I had a friend that came off his bike between 150 and 200 ks.....lucky to be alive. When I asked him why he was going so fast he replied that he didn't realize how dangerous it was and thought he was a better rider than he actually was. I think it's up to the individual to stay safe, cheers Butch Fair point. You mention you have been on bikes all your life but not road bikes, well my worst ever biking accident was solo on a trail bike! As a low hour pilot, and an RPL pilot that only just recently acquired a licence, I tend to keep my mouth shut here. But I often wonder weather the minimum hours are enough. I reckon the hours required to obtain a PPL are probably more suited to an RPL. And its got me buggered how RA-Aust students can get a licence with so little experience. Not only that, but I have met quite a few RA-Aus pilots and have walked away shaking my head in disbelief at some of the stuff they have said. But like I said, I am only new to the whole flying thing, so maybe my lack of knowledge in the area makes my opinions unjustified? I dont know, still trying to figure it all out. 1 2 1
BLA82 Posted June 25, 2015 Posted June 25, 2015 Turbo, That hole is getting deeper "just sayin" 1 1 1
Phil Perry Posted June 25, 2015 Posted June 25, 2015 Well in this case, being an Instructor, there will be W&B sheets. Beat me to it there Loz,. . .I was going to say re-read Kasper's post, the fixed hang point takes care of balance. As to loading, that is another matter. I have been rolled sharply into a steep bank angle on take-off, ( as well as a couple of landing approaches. . .) and pulled towards a tree line by crosswind rotor effect on a few occasions, even when the wind appeared to be fairly light, and it can catch you out really quickly . . . . I won't go into a longwinded raga on three axis to trike control conversion as everyone seems to have a different take on that subject, but just say that the "Bar reversal" mentioned above in pitch control is vary rare in my experience, maybe not in that of others. The "A" frame is solidly attached to that wing, and each control imput feels "natural," and if you ride motorcycles, it's even easier ( IMHO) to get into, as it is simply shifting weight and very similar to handling a bike, ( apart from the upandowney bit that is. . ) UK flying training organisations have adopted a Minimum of FIVE HOURS control variance training with a qualified mentor, some folks take longer . . . . ( especially if they've never been a hell's angel ) This also applies incidentally, to training on moving from trike to stick and rudder. . . ***Edited to add*** One thing a trike will teach a pilot is to be a lot more careful on landings. . . .since the machine has no pilot YAW control at all, if you are landing with a crosswind, the aircraft's longitudinal axis will stay pointed doggedly into the prevailing wind and you will have to land "Skew-Wiff" without tipping the beast over. The older, lightweight flexwings are easier to sort in this regard, because when you become an absolute ace, ( if you live that long ! ) it is possible to drop one mainwheel onto the ground first, thereby pulling the pod around a little so that you don't suddenly wander off the runway aliignment at a great rate of knots ! This is where "Some" 3 axis drivers go wrong, in using the nosewheel steering pedals like a "Rudder" and pointing the nosewheel along the rwy centreline with the trike pod still skewd into wind. . .this can be quite a bad thing to do ! When I converted many years ago ( 1987 ) my Instructor used to keep banging on the back of my helmet and yelling "Stop using the bloody rudder you ********* " ( fill in space accordingly ) With due respect to the topic here, My condolences to the family and friends of the pilot we have lost. Phil
Phil Perry Posted June 25, 2015 Posted June 25, 2015 To steer a bike it is weight shift to steer a plane you use controls. Ok now I see the resemblance. Cheers Good resemblance,. . .in fact it is a fact. . . . So,. . .when you see a bend coming up and you're doing around 160 Kph on your bike, . . .you don't sit upright and turn the handlebars do you,. . .no, you lean into the turn to keep it balanced, as you have rightly said that this is "Weightshift" well, in a trike, the principle is the same Sir. . . you move the bar, to initiate a turn, the wing is initially flying level,. . . .the weight of you and the underslung pod moves in the direction you want to turn. . . the wing then responds and you have a bank angle, balanced with pitch input ( sometimes adding power) to maintain your altitude. . .then you apply more, or less sideways pressure to maintain the bank. The machine doesn't understand aything else. . . Yes, you do use the controls to steer a trike type aeroplane, with your weight . . .mate. . . . And NO I'm not taking the pi$$ either. . . . Dunno how far back the RF database goes, but I wrote a post a couple, maybe three years ago entitled "The Flexwing Ying - Yang" . . .this describes the effect you can get when landing skewly - wiff in a crosswind. . . . never know, it may still be there !
Guest Andys@coffs Posted June 25, 2015 Posted June 25, 2015 Fair point. You mention you have been on bikes all your life but not road bikes, well my worst ever biking accident was solo on a trail bike!As a low hour pilot, and an RPL pilot that only just recently acquired a licence, I tend to keep my mouth shut here. But I often wonder weather the minimum hours are enough. I reckon the hours required to obtain a PPL are probably more suited to an RPL. And its got me buggered how RA-Aust students can get a licence with so little experience. Not only that, but I have met quite a few RA-Aus pilots and have walked away shaking my head in disbelief at some of the stuff they have said. But like I said, I am only new to the whole flying thing, so maybe my lack of knowledge in the area makes my opinions unjustified? I dont know, still trying to figure it all out. Just remember that the hours stated are all minimum hours and no one gets a certificate until they can demonstrate proficiency to the school cfi. If you ask here who got a certificate with the stated minimum hours I suspect there will be a deafening silence Andy
Pearo Posted June 25, 2015 Posted June 25, 2015 Good resemblance,. . .in fact it is a fact. . . .So,. . .when you see a bend coming up and you're doing around 160 Kph on your bike, . . .you don't sit upright and turn the handlebars do you,. . .no, you lean into the turn to keep it balanced, as you have rightly said that this is "Weightshift" Actually, the leaning part on the bike is more about keeping the bike in balance, think rudder and centering the ball. You steer with the handle bars, contrary to most peoples thinking. If you want to turn in harder, you actually steer the opposite way on a bike. Leaning stops you from getting tossed off the bike in the opposite direction of the turn. 1
turboplanner Posted June 25, 2015 Posted June 25, 2015 Turbo, That hole is getting deeper "just sayin" Just so we get to the bottom of this, I've taken some advice from a trike owner on terms, so there is no mistake on what we are talking about. COG of the Hang Point We'll leave aside Kasper's multiple and moving hang points which add further complications, and just consider that the Hang point is within the Manufacturer's Base Hang Point Limit, and also consider that the trike has been correctly assembled. What CAR 233 specifies is "Responsibility of pilot in command before flight" - part of your preflight P&O planning. As we've heard, even a three year old can understand that the Pod hangs from the Hang Point like a swing at positive G, like a pendulum, and we understand also that this is a weight shift aircraft where the pilot moves the Pod, like a pendulum, and that the COG of the Hang Point does not move, so therefore, when fixed within the manufacturer's Base Hang Point Limits, is not part of the CAR 233 calculation requirement. COG of the Pod The net COG of the Pod is determined by a number of component, passenger and luggage COGs I'm aware of statements from some people and even some manufacturers that this doesn't matter. However those statements are contradicted in black and white in the same manufacturer Type Certificate and POH And that's what will count with CASA in any investigation. A Statement like "Solo flight permitted from front seat only" is unequivocal. It is saying COG IS critical Same goes with the minimum front seat weight of 50 kg Same goes with the maximum front seat weight of 100 kg Same goes with the maximum rear seat weight of 100 kg Same goes with maximum baggage under the front seat storage of 2 kg per bag So you do have to weigh the pilot and passenger, you do have to weigh the baggage and you do have to write it down and keep it for 6 months. That is the balance part of W&B Andy has said that he was taught to manage weight, not balance. If W&B is too hard to get your head around, you can call it W&W However, if you want to add fuel pods, camping equipment, tool boxes etc, you first have to work out the manufacturer's COG position of the human body, and work with equations. 1
turboplanner Posted June 25, 2015 Posted June 25, 2015 Filling out what ? The requirement is to operate IAW the POH e.g.1 pilot (<= max weight) + full tanks + <= 70kg equipment = compliant with MTOW. Filling out your flight preparation form and keeping it as a record for six months, in accordance with CAR 233 On that form needs to be what I posted in the last post, plus a lot more information (See CAR 233, CAR 235) 1
ev17ifly2 Posted June 25, 2015 Posted June 25, 2015 Having ridden, raced and sold motorcycles for over 40 years I can tell you that you are both partly right however maybe we should move the discussion off this thread. 1
bull Posted June 25, 2015 Posted June 25, 2015 Know a bit about W&B and thrust lines Kasper? Turbo ,dissappear mate ,your money making schemes are not working 2
kasper Posted June 25, 2015 Posted June 25, 2015 Just so we get to the bottom of this, I've taken some advice from a trike owner on terms, so there is no mistake on what we are talking about.COG of the Hang Point We'll leave aside Kasper's multiple and moving hang points which add further complications, and just consider that the Hang point is within the Manufacturer's Base Hang Point Limit, and also consider that the trike has been correctly assembled. What CAR 233 specifies is "Responsibility of pilot in command before flight" - part of your preflight P&O planning. As we've heard, even a three year old can understand that the Pod hangs from the Hang Point like a swing at positive G, like a pendulum, and we understand also that this is a weight shift aircraft where the pilot moves the Pod, like a pendulum, and that the COG of the Hang Point does not move, so therefore, when fixed within the manufacturer's Base Hang Point Limits, is not part of the CAR 233 calculation requirement. COG of the Pod The net COG of the Pod is determined by a number of component, passenger and luggage COGs I'm aware of statements from some people and even some manufacturers that this doesn't matter. However those statements are contradicted in black and white in the same manufacturer Type Certificate and POH And that's what will count with CASA in any investigation. A Statement like "Solo flight permitted from front seat only" is unequivocal. It is saying COG IS critical Same goes with the minimum front seat weight of 50 kg Same goes with the maximum front seat weight of 100 kg Same goes with the maximum rear seat weight of 100 kg Same goes with maximum baggage under the front seat storage of 2 kg per bag So you do have to weigh the pilot and passenger, you do have to weigh the baggage and you do have to write it down and keep it for 6 months. That is the balance part of W&B Andy has said that he was taught to manage weight, not balance. If W&B is too hard to get your head around, you can call it W&W However, if you want to add fuel pods, camping equipment, tool boxes etc, you first have to work out the manufacturer's COG position of the human body, and work with equations. Not sure how deep a hole is your preference but it seems to be fairly deep ... 1. Do not put aside multiple and moving hang points EVERY wing has them 2. CofG of the hang point is a complete misunderstanding as it relates to the CofG of the the trike unit. The hang point is NOT a CofG and the aircraft or even the trike CofG is not fixed in relation to it. 3. Manufacturers type certificate using CofG calcs???? Hmmm lets just randomly choose one of the Airborne microlights - CASA type certificate No VA513 - Airborne Edge XT 16 December 2004 ... NO CofG limts stated in there ... there is a HANG POINT LIMIT but NOT a CofG limit ... maybe because when I pull full bar in the aircraft CofG moves forward (pitchdown) or push bar out and CofG moves back (pitch up). Now absolutely the combination of the physical limitation of how far you can move the bar forwards and backwards combined with the hang point limits combined with the total mass in the trike effectively IS controlling the CofG within a controllable range with respect to the CofL of the wing BUT provided you are under MTOW with load in the trike YOU CANNOT BE OUTSIDE A SAFE RANGE and so W&B calcs are not done and are meaningless as the CofG MUST be variable at all times because thats how we control the aircraft. 4. solo flight from front only - actually NOT critical from a balance perspective - you WILL have horrendous swing through and the trike attitude in the air would be bizarre BUT there is not full dual control for engine , brakes, flight instruments etc in the rear seat so the requirement is a valid limitation but not for the reasons you think 5. baggage under seats is not a W&B issue - its a can the container restrain the load in a 9+g accelloration test - its not W&B its strength of containment 6. before you ask why there is a lower limit on front seat - YES the trike hangs differently at different weights and at extremes the bar position in relation to the chest of the individual may result in less than full and free movement but usually is is the limit that places the bar in the classic piano playing position at free bar position - again the limit is not related to W&B but another separate operational consideration. And finally - if you are admitting that it really is W&W on trikes - I'll do the eliminations of that equation as if it were mathematics - ummmm so its WEIGHT limited ... and strangely I think that's what EVERY trike pilot has been saying to you from your first post on this tread. Personally I feel the hole you dug is now filled - would you care to start another? 1 1
turboplanner Posted June 25, 2015 Posted June 25, 2015 No, I've quoted you official data. What you do is between you, RAA/CASA,or the end result As for the CoG of the hang point - CoG of the down-force at the hang point if you prefer. 1
kasper Posted June 25, 2015 Posted June 25, 2015 Filling out your flight preparation form and keeping it as a record for six months, in accordance with CAR 233On that form needs to be what I posted in the last post, plus a lot more information (See CAR 233, CAR 235) "The pilot in command of an aircraft must not commence a flight if he or she has not received evidence, and taken such action as is necessary to ensure, that: (a) the instruments and equipment required for the particular type of operation to be undertaken are installed in the aircraft and are functioning properly; (b) the gross weight of the aircraft does not exceed the limitations fixed by or under regulation 235 and is such that flight performance in accordance with the standards specified by CASA for the type of operation to be undertaken is possible under the prevailing conditions; and © any directions of CASA with respect to the loading of the aircraft given under regulation 235 have been complied with; (d) the fuel supplies are sufficient for the particular flight; (e) the required operating and other crew members are on board and in a fit state to perform their duties; (f) the air traffic control instructions have been complied with; (g) the aircraft is safe for flight in all respects; and (h) the aeronautical data and aeronautical information mentioned in subregulation (1A) is carried in the aircraft and is readily accessible to the flight crew." So I as a trike pilot comes up to this one for a flight 1. received evidence = I have evidence of - does not require me to document it or get it from another person 2. gross weight under limit = eg for me, I know the aircraft has a free load limit with full fuel of 205kg - I know that in helmet and flying suit I weigh 95kg, I know that so long as I am loading the rear seat and the under seat storage (in accordance with individual location limits) with less than 110kg of other stuff I am legal. I do not have any declared W&B issues from CASA under 235 so I am legal so long as I have evidence that I am under MTOW 3. AIP data under 1A is always a fun one for open cockpit - and more so when it s pusher engine, you REALLY do not like to see what happens when things hit that prop. And as for the requirement for the OPERATOR to retain the flight preparation form in 233(3) lets apply law school 101 and realize that the flight preparation form referred to is the form required to be created in 233(2) to record for international flights evidence of the items in 233(1) ... A domestic flight does not have a 6mth documentation retention requirement under 233 because it only require the pilot receive evidence not record that evidence, 235 does not import a W&B calc for trikes (just weight) so basically you are wrong on all counts. Can you confirm that this hole is finished with? 1 2
kasper Posted June 25, 2015 Posted June 25, 2015 No, I've quoted you official data. What you do is between you, RAA/CASA,or the end resultAs for the CoG of the hang point - CoG of the down-force at the hang point if you prefer. Nope. CofG is the centre of mass of the airframe as a whole - for my trike 56kg of that weight it in the wing and to calculate the point-in-time CofG you would need to work out the mass moment of the wing and the mass moment acting through the hang point of the trike ... I am seriously concerned you are wearing out a shovel with all this digging, would you like us to start a collection to get you a new one? 1 1
turboplanner Posted June 25, 2015 Posted June 25, 2015 No, I think you've uncovered yourself enough now. CoG simply means centre of gravity.
facthunter Posted June 26, 2015 Posted June 26, 2015 The "Load Sheet" is an active document for the flight as you need to derive landing information (Weight and Cof G) based on actual figures for landing. Divert or holding will give different landing weights from planned. Useable fuel cannot be used to keep in balance. There are exceptions for that in complex transports (Concorde) but as far as we are concerned NO.. Nev
Guest asmol Posted June 26, 2015 Posted June 26, 2015 BUT, if you put say 200 kgs in the back of the trike by adding luggage, doubling the fuel qty etc all at the rear, the thrust line will obviously be different because the trike base will hang differently and you may run out of bar movement because the bar will be in your stomach when flying straight and level. So YES loading a trike will have a big effect on how it flies, this is something you cant argue about, its a basic law of gravity with the base hanging from the bejesus bolt or whatever its called. If all the weight was at the front then the bar would hit the tube in front of your trike and control is lost the other way.
kasper Posted June 26, 2015 Posted June 26, 2015 BUT, if you put say 200 kgs in the back of the trike by adding luggage, doubling the fuel qty etc all at the rear, the thrust line will obviously be different because the trike base will hang differently and you may run out of bar movement because the bar will be in your stomach when flying straight and level.So YES loading a trike will have a big effect on how it flies, this is something you cant argue about, its a basic law of gravity with the base hanging from the bejesus bolt or whatever its called. If all the weight was at the front then the bar would hit the tube in front of your trike and control is lost the other way. Oh dear - another hole digger :-( 1. how do you suggest doubling the fuel qty? 2. jerry cans of fuel (even metal ones) are physically so large that you could not get more than 100kg of them onto the rear seat ... even with my special 65L rear seat tank system fully filled and plumbed into the lower tank I am only putting 57kg of load on the back seat - and that tank fills the entire seat front to back and side to side and it is nearly as high as the shoulders of a passenger. 3. EVEN if I COULD get 200kg of stuff on the rear seat the bar position WOULD NOT be on the front strut - the rear seat masses are within a couple of cm of the hang point BY DESIGN to make the rear load practically unimportant from a bar position perspective. Take a look at the trike in my profile - the main mast comes forward and links/hangs pretty much over the rear seat. So again, I come back to the fact that IF you remain under the MTOW the load distribution will not adversly affect general control. And EVEN if you disregard the MTOW and put very large weights in the rear seat it STILL will not move the bar position. And the physical size limits of what you can put in the rear seat means its VERY difficult to come up with a way to actually get 200kg on the rear seat. So no, loading a trike within its MTOW on any practically available place on the trike WILL NOT have a big effect on the way it flies. 1 1
pmccarthy Posted June 26, 2015 Posted June 26, 2015 Gold bars. Just a few on the back seat would put you over the limit. Don't use a trike as a getaway vehicle when you rob the mint. 3
Guest asmol Posted June 26, 2015 Posted June 26, 2015 EVEN if I COULD get 200kg of stuff on the rear seat the bar position WOULD NOT be on the front strut - the rear seat masses are within a couple of cm of the hang point BY DESIGN to make the rear load practically unimportant from a bar position perspective. This is what i was asking, Would 200 kgs in the back seat THEORETICALLY make a difference BEYOND what you could control ? You have answered that question but what about the thrust angle change. Does that have an effect. Dont shoot me for asking, just trying to understand. I would have thought if you hung a trike by the bejesus bolt in your hanger without a wing and placed all those gold bars in front of your feet, or had someone (in theory) sit on the pod would that change the angle 5 degrees, 30 degrees or 60 degrees ? I guess i could work it out if you knew how far to the edges of the airframe in each direction. The original question was about overloading, IF you put say 2 cans on the side of the existing tank, which i have seen done like saddlebags, loaded up the nappy, grass catcher thing underneath and then put all your gear in the back seat would that make the plane unflyable ?
turboplanner Posted June 26, 2015 Posted June 26, 2015 The angle change can be calculated asmol, but Kasper, after some early boasting has been too busy throwing dirt to do it. 1
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