Yea , stir things up , you work your way through the inane drivle & the odd piece fits . Further steps along the path , as it were .
Flying the second hourglass corner ' Hard ' ( slamming it - on - off at the handle ) is not a good idea .
flying it either slow to full , and slow off , for the top leg . As in a measured deliberate ' easeing ' to find the breakaway point ,
or flying the corners as rounds - to see if it the carries tension even through the lot - Sometimes you get your arm full out -
by the first top corner - and draw it down as you go across , stepping aft as you turn into the downward leg .
Tip weight . Turned to Al rabe & hit ' show all posts' . tho like usall , He gets off track a bit or Has his own perception ,
theres some thought through trails of explanation / logic - Enlightening as to aerodynamic effects & mass / inertia / & reactive resultant THING .
theres only four pages - I printed off one or two - He gets into reverse props - a bit . And TIP WEIGHT . If you throw too much in , get hingeing , then pull it back .
But in windy kiwiland , a hint off hingeing keeps you going . Rather than spinning out and piling in . ( Like a certain bue aeroplane could snap into )
https://stunthanger.com/smf/profile/?area=showposts;u=882Is your plane a ' Two Much " , with adjustable leadouts ? . ( My Spitfire - engine Swapping - St 60 /51 SF46 seems a bit critical on C G , with fixed leadouts . Spot On ( matched )
it does marvelously . Nose or tail heavy it starts yaw roll . Tho it needs the toolbox sitting on the inner wing , plane inverted . Beforehand . Wash IN on the inner screwws it compleetly .
A degree and a half washout on the hurricane semi acale . It Floated through the top of the Vert. 8 ( Outside loop over 45 deg . As in ' Sailed through Nicely ' all by itself , so you could ' catch'
the reversal point at the handle for the lower inside , as iff you had all day . This THING was V good , undisturbed - By reasonably steady highish winds . 15-18 and steered good in even higher .
The discernable wash out on the low wing layout presumeably was a major contribution .
Seventeen months passed before engineers were able to determine what caused the Lightning's nose to drop. They tested a scale model P-38 in the Ames Laboratory wind tunnel operated by the National Advisory Committee for Aeronautics (NACA) and found that shock waves formed over the wing when the airflow reached transonic speeds causing turbulence. Also the aircraft nose would tuck, because the downwash over the tail diminished, creating greater pressure on the bottom side of the horizontal stabilizer. This could be remedied by adding full elevator up trim, and sometimes the aircraft would recover at lower altitudes as the air density increased.
Blah de Blah . Ive tended toward the + tailplane incidance , on the highish placed tailplanes . He rattles on about longitudeinal diheadral , incience & downthrust , on a longer post ( I just checked a few longer ones there )
I think , maybe , if youve gone Zero zero Zero , theres your culprit . It may need the old 3/16 across the full surface , back there . You put a L O N G stick across it - fore & aft . Or two , ea side , pack parrallel .
to see she's say 1 1/2 degree positive .
you generally gottra run offset on the outer . inboard stright , maybe . ( depends upon the ship - the more side are little ones seem way more consistant ) THOUGH the big P 38 was too , with naff all side area .
Next One ? will have fixed Outer Tailplane ( outside booms ) as i think itll work better like this . Make the pilot less strung out .
I take it its ' dropping off on a wing ' into the top leg , up there ? ( Still steady through the top of the Vertical eight though ? ) Id built the P - 38 to fly clockwise - cause off the dual tourgue prop bit ,
Havving been having the Mosquito flying the pilot on occasion .
So THATS an Answer , Too !
Same wing ,, ( 6 in shorter , thinner same airfoil ) on a Mewgull , in a stiff steady breeze , would increse speed ONLY ( really ) in the Square eight , faster out of each turn . THE POINT BEING
it ' THREW ' the outer , in the last center top turn . AS IN - it did a big gyro yaw and put the outer up a foot . and the inner down a foot . IMEDIATELY picking itself up , Straight before 1/4 of the top leg was done .
Nuther drivle was in massive cross wind - downfield to 50 foot alt. Across diagonal above - wind shear / two distinct levels . this thing would sail round in a deep 4 stroke - on 15 or 20 %nitro on a 12 x 6 .
AT the wind shear Level in the ' downwind ' leg off the overhead eight = Massive ' ROCK '- One Sine cycle . i think near 18 in down the 12 in up inner tip . scarey. At First . but as it gave a BIG TUG at the handle
as it did it .
It Wasnt a trouble . in retrospect .
First time did a O Head , when the engine had settled in , Thought I was going kite Surfing . Needs a Distinct restraint on the muskly arm . Pulls It to full stretch ! otherwise .
Blahdy Blah .
Center OFF Cravity . The liddle Phntom wiff za Lost Motion 3/16 slack at the T E , runs the C G 3/4 Aft on the plan its a rip off of . Grooves & turns V well . get rid off the orrible slack , and it wont do nuffin proper .
no Matter what .
THE IDEA being . try throwing the C G BACK ( use (extreeme ) caution ) and conversely , Fwd . A couple off ounces strapped / taped ( plasticine ? ) on the nose . Try 1/4 oz or something - try it 1/4 & 1/2 inch aft ,
off where your at . Tetitively . See if it jumps around and bites . Or starts purring and rubbing your legs
Like the Mosquito . BEWARE - Danger will robinson. Danger . etc . It Its Tryn to put ITS NOSE IN .
the Arm Out , Flick off the wrist , AS You Side Step - right left - one pace - aS YOU TURN into across and draw arm down , and step aft into the downhill corner . AAARRRGGGHH . Literal .
rough the Phantom'd cut loose and make ya run TWELVE TIMES in a Flight . After you got back from the townies Torture Treatment . Steeping Clear , Taking several deep breathes , and muttering smoother smoother
after youd opractised your Ballwet steps ( with noone looking ),
We might exagerate a bit their .
BUT
it was the Phyce ' ahead of it ' slight easy 7 light touch , at the HANDLE that would get you through ANYTHING .
Whereas The Big Long wing thing's , HAMMERING the Lower Turns , and then others , in Squares and wingover,
was the norm , Easing OUT of the lower corners , and it'd have no bobble . Slamming em , 50 % either Way .
good or Bobble , So the EXIT from the Square was where you needed to pay attention - Concentaqte . Particly when tail heavy .
one further last rattle - the excellent little red TWIN . one muffler fell off , & it had a slight porpoise , Both & da Definate . Level at four or five feet Alt. Flat .
One and it'd eaee at ten foot . both a bit higher to sit striaght .
The VETERAN ' old time stunt ' GROOVE ALTITUDE . = = = = = center of gravity = = = = = Maximum Aft . = = = = = TEST
All this full size shert , they ESTABISH the Maximum aft. C.G. LIMIT .
As it goes back , somewher the stability starts going DIVERGENT .
as in it POROISES . ( waggles the stick , your head & neck . then trys to throw you throughj the canopy )
In this Book , he talks about POSITIVE STABILITY being a prerequite to SMOOTH CONTROLED aerobatics . Aft C G & it jumps about like a jellyfish .
SO , Thrustlines . vert & Horizon. CHECK .
Rear End incidance CHECK .
Explore and establish Working C G . tickly with respect to Dead Zone elevators or & free controlled movement of FLAPS . ( for groove ) BEFORE elevator starts moving !
Typically Hold the elevator - and the flaps go 1/8 before it cuts in . FLAPS HELD SECURE - 5 mm freeplay 2 elev. T E . equal about neutral .
i put a flattened brass bush , in the elevatorn horn , on the p 51 , and it cured its waywardness . Means you can SLAM a Corner & it EXITS CLEAN .
As your nervous reactions at the handle , are only controling the Flaps / Lift . NOt the Pitch of the fuselage . So she dont porpise , turns hard , and exits clean , on an aft Center of gravity . MATE .
and seems less critical of leadout setting with it ! And Dont forget the TIP WEIGHT TEST .
read through Al's diatribes , before endevouring to digest other than the Salient Points . They always have sore heads , downtown . rouch grouch grouch .
ACTUALLY , these things shifted line , if you shifted the throttle , till they stuck bigger surfaces aft , when they had any power . so If its a bit vintage and smaller than 20 % Tail , its in the ' narrow trim ' range .
and Loose Elevator'd HELP .
Topic: Twin Prop Direction (Read 2186 times)