Pilot Notes For "Flying Flea"
HM 290/3 FB
By: Kirk Sutton
REG. No. 1438
1) flea is a tailwheel aircraft
2) steering is by pedals ("rudder" pedals)
3) pedal travel is very short
4) first 2/3 rd travel is tailwheel only.
5) last 1/3 rd travel is tailwheel + differential brake
6) due to set up of flea-cofg is a long way behind main wheels- swings easily
7) Wheel base is short-swings strongly.
* on the ground is slow taxi forward vision is poor directly ahead due to engine but adequate vision exist by looking out each side-steering is quite positive.
* on takeoff (using flap) tail wheel steering is positive and good right through the take off roll.
* on landing (with or without flap) the aircraft is very liable to start swinging with the swing into ground loop strongish.
1. don't jab pedals --> brakes may bite
2. if its not 100% straight on/in the landing flare go around.
3. once on the ground there is a large 'top dancing' on the pedals.
4. ground roll is short --> landing happens very quickly = 5 seconds.
Engine Handling1) 503 is a 2 stroke idle = 2000
full power on climb = 6000
full power straight level = 6800
cruise power 5200 = 5800
power approach 4000
2) power increases * decreases must be progressive --> rapid increases may cause engine stoppage.
* esp. with black cruise prop.
1) takeoff roll is short
2) a) set 1 stage flap (5 degrees)
b) line up --> roll straight to ensure tail wheel is straight.
c) add full power (= 6000)
d) stick forward to minimize during on front wing = 2/3 forward travel
e) swing is to right --> stick to the left = 1"
f) aircraft remains on all three wheels until 45 knots --> gentle pull back
g) once in the air let speed settle to 50 knots --> weight on stick = 2-3 lbs back pull with stick slightly to the left of center.
h) nose is very high, higher than ground attitude.
i) once 3-400 feet set flap at 0 degrees and climb @ 45-50 knots.
3) you can't stall the aircraft with full power and 1 stage flap; it just stops climbing and 'bobs' its nose but weight on the stick is higher below 45 knots.
4) if it starts to roll from side to side you must stop it by positively holding the fore-aft stick position for climb speed and holding is side stick of = 1" to commence a turn (either way) and it will stop. NEVER make rapid side to side stick moment to stop uncontrolled rolling.
1) Recommend powered/flap approach to start with.
a) get power on base to 4000 and extend 1 stage (5 degrees)
b) fly a "drifter" like circuit.
c) settle speed to 60-65 knots for approach.
d) on final just use power to adjust descend --> but no longer than 4000
e) over the flare approx. 20 feet.
f) commence flare as normal by pulling back on stick gently/ progressive
g) Must be straight or go around
h) as wheels touch throttle dosed and stick full forward.
i) touchdown is = 40-42 knots but speed isn't essential as this flap/power settles the flea --> it will not balloon.
2) Flaps 0 degrees landing is the same as above but flea will float a bit and tailwheel steering once on the ground is not a positive until it slows down. Might swing first.
3) glide approach --> exactly the same as 1. except best glide speed is 55-60 knots (ideal).
a) glide is very poor-worse than drifter.
b) suggest that 'real' glide approach use 60-65 knots as its more powerful in the flare and landing roll is still short.
"Stalls" --> unloading - pitching - loading.
* The flea is set up as a canad type aircraft with the front wing being more heavily loaded (due to stick gofg limits) and having much higher relatives angle of attack to rear wing.
*As a canard the "stall" sequence is :
a) pull back on stick
i) aircraft initially climbs in same attitude
ii) aircraft starts to slow
iii) aircraft starts to pitch up ( loss of lifton rear wing).
iv) weight/back pull on stick increases noticeably.
b) front wing starts to 'stall' which in noticed as "booming" from wing skins and strong shaking in the stick --> continue to pull back on stick.
c) weight on stick increases until the front wing unloads after the "stall" of that wing.
d) nose lowers and front wing has lower Aof Attack => u-stalls sequence repeats with nose "bobbing" up and down gently.
Specific stall info.
no flap. --> front wing acts as full span slot to rear wing increasing the lift on rear wing. This means that this type of stall is the gentlest and with medium to high power (5600-6200) there is no height lost. The nose is quite high and unload/lowering of nose happens at full back stick.
5 degree flap --> much the same as no flap except weight on stick is greater and unload may occur just before full back stick. Nose altitude is slightly higher and the nose 'bobs' a little lower than with no flap.
10 degrees * 15 degrees flap --> slot effect doesn't appear to be as pronounced. With these settings the stick moves to full forward and at medium to full power the aircraft will settle to climb in a "stall" load/unload bobbing of the nose.
If you pull back on the stick full load/unload stall occurs same as for no flap /5 degrees except nose is higher, weight on stick higher, shaking more pronounced and on unload the nose lowers quite positively to around 10 degrees nose down.
20 degrees flap --> slot effect is not noticeable and the aircraft 'appears' to stall as per a 'normal' aircraft with a very steep nose up attitude with rapid nose down pitch. => approx. 40 degrees nose up to 20 degrees nose down in about 1 second. As soon as you release back pressure it starts flying straight away.
speeds indicated for "stall"
0 degrees - just under 40 knots <=== no loss of height
5 degrees - about 40 knots <==== if power is on
10 degrees - about 35 knots <== slight loss of height with power during the bobs
15 degrees - about 35 knots <== slight loss of height with power during the bobs
20 degrees - under 35 knots = 32 loss of height with bobs = 50 feet
Fleas have no direct roll control via aileron. But the secondary effect of rudder is very strong due to short span and very low aspent ratio (=3.2) infact the primary effect of you is not noticed as the flea rolls with the yaw.
Fleas have rudder on the side stick movement where you would expect to find ailerons.
NOTE: rapid side movement are to be divided in initial flights because the speed of movement affects the amount of delay in the roll effect and the rate of roll.
general turns are by gentle smooth movement of the stick in the direction of the turn with the side stick held into the turn.
* different from 'normal' planes in this respect. Fleas instantly start rolling out of a turn as soon as the slide stick is removed/relaxed.
* because you cant hold rudder against the turn you cannot do very steep level turns or stall in a turn because the fleas just enters and holds the correct angle of bank in a descending turn for the rudder held. Rolls instigated by rapid movement of the stick into a turn have a delay or lag between the input and the roll --> but when it starts it rolls quickly if you hold in the side stick.
* After you are comfortable with the flea demonstrate that it is stable as follows.
1) in straight flight @ = 65-70 knots
2) rapidly move stick left and right without holding it at side for any time.
3) The Flea yaws minimally but doesn't roll.
Why? --> because by the time the roll should start after the lag the rudder is already opposite. i.e. without holding in side stick there is no roll.
heading control yaw.
As rudder creates rolls in the flea you cant hold any degrees of slip and the only way to alter heading/yaw is to actually make a turn onto the heading you want. Its a little imprecise at first so this is an additional reason to do powered approaches to start with, final is longer and you have more time to get it on the runaway heading.
This Flea does have definite pitch attitudes, the change from 'normal' aircraft is that pitch attitude of the fuselage is not directly affected by fone-aft stick movement which directly pitches the whole front wing A of Attack but is secondary effort of speed at all flap settings as the fixed angle rear wing relative to the fuselage creates more/less lift proportional to speed which provides an up/less up force on the rear of the flea. The flap increases the nose up pitch at any speed due to its dumping or lowering of the lift on the rear wing --> accomplished by decreasing the effective A of Attack of this wing relative to the fuselage.
"standard" pitch attitude of fuselage.
reference --> "Normal" ==> ground attitude.
climb @ 45-50 knots ==> slightly higher than normal attitude. (about 10 degrees)
straight * levet @ 65-85 knots =>level
descent @ 65 knots @ 8000 rpm => about 10 degrees down
climb @ 45-50 => slightly higher than no flap climb => = 15 degrees higher than normal.
descent @ 65 knots @ 4000 => about half way between level and normal.
in stalls the pitch attitudes are as described in the stall section above.
No notes at the moment, leave them alone till comfortable with the general handling of the flea.
straight and level can be maintained at any speed from 45-87 knots on various power settings. Below 60 knots there is a noted pitch up nose attitude above 60 the fuselage is basically level.
Top speed indicated in S*L is 87 knots @ 6300 rpm
- this prop is slightly over pitched
- be aware on low-mech power
i.e. below 5200 rpm pulling back on the stick loads the engine and it starts to die away ==> it Must be power --> Attitude if you pull up in other respects it is normal.
Pitch --> the aircraft is pitch stable with no difficult in holding a desired wing position/speed. Without a trim device stick for stability can only be tested in the 10-20 degrees flap position where the stick naturally goes full forward. In this condition it is positively pitch stable with return to stable "bobbing" of the nose.
Yaw--> this flea will maintain heading without any "snaking" at speeds up to 60 knots. Above 60 knots the aircraft becomes progressively less stable and tends to shake slightly due to minor movement of the stick which is divergent i.e.. it becomes progressively move snakey and increases left/right with the stick wanting to warder with the yaw which is accomplished by roll. This is easily controlled by positively holding the stick controls and countering yaw/rolls as they develop.
* roll--> at lower speeds (up to 60 knots) the aircraft is positively stable in roll and returns quickly to level flight. Above 60 knots the roll is still stable but combined with the 'snakey' yaw issue where the rudder tends to float from side to side inducing a roll which becomes divergent and progressively larger.
* LARGE RUDDER WAS FITTED THINKING IT WOULD BE NEEDED TO HOLD HEADING WITH SPOILER DEPLOYED THIS CAUSED ' SHAKEY' ACTION. SMALL RUDDER REFITTED 'ALL OK' IT WAS ONLY ONE FOOT LARGER.