Graham,
I have the VG test flight and a proposed install manual that went
nowhere at Europa on my website today.
(www.customflightcreations.com<http://www.customflightcreations.com/>
click on techniques articles.) I had a manufacturer make the VGs with a
curve on the bottom to fit the wing. I also use a 3M glue that doesn't
make a mess and you can reposition them or if you don't like them, pull
them off with no paint damage. Right now I am finishing Cooling 102 for
the Jabiru installers and trying to finish a really screwed up airplane.
I hate redo's. Enough complaining. On to VGs.
On your canards, I believe the VGs are a must for better pitch control
and on swept wings keep the ailerons corraled.
On the Europa, VGs do slow you down about 10 knots but since I don't run
around at max continuous doing 146 Knots and burning tons of gas, that
doesn't bother me that much. I have had the VGs off for the last two
years while I redo some propeller testing for Airmaster and frankly my
wheel pants are too low for rough grass so I've stopped STOL / LSA
testing. The trigear really doesn't like bumpy rough grass strips so I
need to get back to testing on grass so I can get a feel for if I need
larger tires.
I only put the VGs on the upper surface of the wing. I must admit that
I thought about changing the stop imits of my stab and putting the VGs
on it as well, but right now with the VGs on the wing only, my poor old
classic has scrape marks on the rudder and spats from the asphalt and I
still have stick left at 40 KIAS (CG at 60, +13 up -5 down on stab.)
What it does, is allow me to give someone with an unfinished kit the
ability to lower his clean stall to 45KIAS, and with a 912ULS or Jabiru
fitted with a fixed pitch prop set at a bit of a mid range, to meet the
LSA stall and max continuous power cruise requirement of 120 (well maybe
a knot or two more depending on pitch).
For those whose short or rough field woes give them worries, the VGs
allow better low speed control, and a lower approach and touchdown
speed. The lower touchdown speed and keeping the nose wheel off the
turf is critical and without VGs on the stab I can keep the nose up on
12AY but on some really forward CG aircraft, VGs on the stab and a bit
of up stab tuning may be necessary. As tested, the aircraft is quite
comfortable slow flighting very close to the stall with supurb aileron
and pitch control, but the deck angle is a bit high on a dragged in
approach. With VGs I can fly a normal 3 degree flight path or steeper
at 55 or so and see my touchdown point and cross the threshold at 45-50
and have enough power and control to flare out to a 40 knot touchdown.
Alas, the mono's deck angle is so low that you can't land as slow as a
trigear, but it sure makes getting the tail wheel down first easier with
better roll control should things go a bit askew.
Read over my two attachments on the techniques articles on my site. At
$130 plus shipping it's a cheap experiment (with lots of extra VGs
should you want more to put on the stab) and a lot cheaper than adding
wing area or trying to build a new classic wing to get the weight down
or change the camber for STOL performance.
Regards,
Bud
----- Original Message -----
From: GRAHAM SINGLETON<mailto:grahamsingleton@btinternet.com>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Monday, May 12, 2014 9:42 AM
Subject: Europa-List: Re: Europa-List: RE: Europa-List: Re:
Europa-List: Re: Europa crash in L=C3=BCbeck/Germany
Bud
excellent letter. I am most interested in your VG installation. Did
you fit to botn wing and tail?
I fitted them to my Long EZ and was delighted with the improvement in
low speed handling.
Graham
-------------------------------------------------------------------------
-----
From: Bud Yerly <budyerly@msn.com<mailto:budyerly@msn.com>>
To: europa-list
<europa-list@matronics.com<mailto:europa-list@matronics.com>>
Sent: Monday, 12 May 2014, 5:28
Subject: Europa-List: RE: Europa-List: Re: Europa-List: Re: Europa
crash in L=C3=BCbeck/Germany
Graham and others.
Good comment on the leading edge curve. My Classic wing has that
slight cup sanded and filled off by my painter. It has a bit of a sharp
stall like a normal series 6 airfoil.
On the accident comments:
I hate to speculate, but the accident investigator training and
extensive flight envelope expanding time I have acquired, leads me to
use caution speculating at this time and to causes and early on
assumptions on should have had equipment, etc.
The initial test phase of the Europa (or any aircraft) needs to make
sure it is made in baby steps.
After building 18 aircraft 15 of which are Europas (yes I am starting
our 16th Europa in the shop) and test flying many other owners aircraft,
many things can cause a takeoff leg stall spin type accident.
My last call from a US accident inspector was a very long time ago.
Here is what we discussed on a takeoff leg, attempted turn back and high
angle impact deadly crash of an experienced pilot and seasoned aircraft.
Off the top of my fuzzy balding head:
On takeoff the Europa has a very good rate of climb and deck angle.
In testing of 12AY (a Classic) with 914, the full flap takeoff has a
deck angle of 10 degrees (and about a 12.5 degree angle of attack) at 55
Knots. When pulling the power back abruptly during test, at 55 knots, I
found only 3 seconds with the nose up pushed me into the stall warning.
Since the full flap approach angle power of the my old Classic is
about 8 degrees glide slope or so, one can see that it requires a 13
degree push over to try to preserve airspeed and control.
Lesson for everybody: Recovery from a takeoff engine failure requires
an aggressive nose down push to preserve airspeed.
Clean, it wasn't much better, in fact with the 914 at 65 knots the
deck angle is close to 15 degrees and the results were a very rapid
bleed off unless a push over to nose slightly below the horizon (about
5 degrees) was necessary to preserve airspeed.
To the comments on the web regarding AOA and flight testing:
A new pilot checking his aircraft out is not safe by adding equipment
to help determine his AOA. These systems require calibration and
testing. I doubt these folks had time to test and calibrate aircraft
systems in flight test yet. Un-calibrated equipment often times leads
to more cockpit distractions early on.
I have no data on this accident and doubt I or we will get much other
than stall spin accident.
My flight test comments are as follows:
We know that in the preflight phase, Annex E for wing angles/tail
plane angles and control throws is not enough. Retract tests are
essential to verify gear lock, flap position/operation, and outrigger
lock operates full proof. The engine and fuel system must be bullet
proof at level and max angle nose up. The fuel system must be able to
go from empty to fully primed at max angle with only 5 gallons total
(the main and reserve side holding 2.5 each across the saddle) in 5
seconds or less. Complete Wt. and Balance and a review of max forward,
aft and test flight loads and CGs verified on the Wt and Bal form. (I
normally will fly with a minimum of 10 gallons US on test flights.) The
engine must run flawlessly idle to full and not overheat on the ground
for 20-25 minutes running at summer time temps.
The electrical system must be able to handle the load, and if there is
a cockpit smoke situation, battery off, the engine must run with
ignition only. (914s don't forget the Aux pump operation.)
All engine instruments and flight instruments/equipment (pitot and
static) must be verified for accuracy and operation prior to flight.
(Read as no red light distractions on takeoff or funky airspeed and
altitude indications). Trim must be checked and verified operational.
All aux systems must be operational or placarded and left off. (Radio
is a must, Transponder is often required, ELT operational, (I turn AOA
and Autopilots off).
The night before, I chair fly and prepare for the flight. I go over
aircraft systems, test parameters, panel layout and specifics of complex
electrical systems.
Flight one is 15 minutes to check for runs drips and errors.
(Immediate acceleration to 75 and climb at 90.) (Normally I can fly one
of our planes hands off, feet only, half way down the 4000 foot strip
above 50 feet.) Climb to 2500 feet or so and check the trim and rig from
70 to 100 Knots. Return to the pattern, 80 on downwind, no slower than
75 in the turns, and no slower than 70 on final. One of two low
approaches if in a mono is OK. Land and pull the cowl and inspect.
Fix any and everything you found abnormal.
Flight two expands the envelope to check engine climb temps and
performance. Check CS prop operation, and climb 3 mistakes high and do
A/S verification, stalls, falls and pitch and roll stability. Typically
our engines are flawless so it is only a 45 minute flight. If all goes
well and we have good stall characteristics, go back and review the
flight. (I have needed stall strips on the root to get a good early
burble feel prior to stall.
Once I am convinced the pilot (who has normally flown in my aircraft
for about 5 hours and is very current in other types) is ready, I
prebrief with him and hand him the keys for a test hop.
However, I have been guilty of flying a test flight early into the
flight phase dual. Confidence in the aircraft has to be extremely high
to do this. A thorough brief of what will happen if the engine quits on
takeoff is a must. The aircraft is the last thing I will attempt to
save. Two people flying an untested aircraft is too much exposure and
sometimes weight. ( My rule is the plane is not ready for test flight
unless you are prepared to knock on the test pilots door and explain her
husband is dead, and there was nothing that you could have done to make
the aircraft safer.)
Typically in the flight phase we go out dual and do stalls, slow
flight, advance handling at minimum speeds and ascertain if the pilot is
comfortable, the stalls are predictable and easily recognized. ( I am
the technical observer who is verifying airspeeds, pitch angles, stall
buffet, system operation and calibration while the client flies.) This
is where the AOA, Autopilot etc. gets calibrated or rung out.
Frankly, my opinion is that an AOA systems in straight wing aircraft
is a waste of money for me and I prefer a well installed stall strip
(swept wing aircraft are different). That said, after the 3rd 300 mile
leg in 90F degree weather, sometimes it is nice to have "Bitching Betty"
remind me that I am not paying attention. Fatigue and complacency do
set in to us all.
If one adds my vortex generators for STOL capability, watch your speed
as the aircraft handles so well down to 50 Knots clean, you could be
falling with style and not know it unless looking at the airspeed. Here
is where an AOA, Airspeed Warner like the Europa Stall indicator, and
proper stall strip can be handy.
Right now all I can do is pray for the families heartbreak and learn
---From the lessons hard learned from previous aircraft accidents and my
own experiences. Then when appropriate, pass on the hard learned
lessons to those who may benefit.
Regards to all,
Bud
-------------------------------------------------------------------------
-----
Date: Sun, 11 May 2014 23:03:53 +0100
From: grahamsingleton@btinternet.com
Subject: Europa-List: Re: Europa-List: Re: Europa crash in
L=C3=BCbeck/Germany
To: europa-list@matronics.com
Graeme
I was refering to the Classic Europa wing. The section has a slight
bump just
under the LE which is very easily sanded off. The nose radius is also
quite small,
again easy to sand off even with a sheet of fine abrasive round the
LE.Accurate
templates are essential and the plans version isn't accurate enough
for these subtle
curves. That's what was wrong with G-KWIP's wing. Always dropped L
wing in a flaps down
stall.
Graham
-------------------------------------------------------------------------
-----
From: graeme bird <graeme@gdbmk.co.uk>
To: europa-list@matronics.com
Sent: Sunday, 11 May 2014, 18:57
Subject: Europa-List: Re: Europa crash in L=C3=BCbeck/Germany
<graeme@gdbmk.co.uk<mailto:graeme@gdbmk.co.uk>>
Interesting to hear that you can fly with a flap down; but for me a
lot is going on just after take off, watching the gauges, the speed the
VSI, changing prop pitch, unlocking to get the wheel up and pushing the
leaver with the right hand etc - maybe the spring/tension is a bit off
if its first flight, I am not sure how I would cope if there were to be
a sudden roll at that point.
Yep I also value Grahams wisdom and contributions; I am just thinking
of the message, unintentionally, its sending to current builders. The
fact is hundreds have been made by imperfect amateurs and the stall
characteristics are one of the first things explored during the test
flights.
--------
Graeme Bird
G-UMPY
Mono Classic/XS 912S/Woodcomp 3000/3W
Newby: 105 hours 26 months on the Mono
g@gdbmk.co.uk
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=423188#423188<http://forums
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