Graham and others.
Good comment on the leading edge curve. My Classic wing has that slight cu
p 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=2C but the accident investigator training and extensive
flight envelope expanding time I have acquired=2C leads me to use caution
speculating at this time and to causes and early on assumptions on should h
ave had equipment=2C etc.
The initial test phase of the Europa (or any aircraft) needs to make sure i
t is made in baby steps.
After building 18 aircraft 15 of which are Europas (yes I am starting our 1
6th Europa in the shop) and test flying many other owners aircraft=2C 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 i
s what we discussed on a takeoff leg=2C 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 tes
ting of 12AY (a Classic) with 914=2C 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=2C at 55 knots=2C 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 d
egrees glide slope or so=2C one can see that it requires a 13 degree push o
ver to try to preserve airspeed and control.
Lesson for everybody: Recovery from a takeoff engine failure requires an a
ggressive nose down push to preserve airspeed.
Clean=2C it wasn't much better=2C 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 u
nless 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 he
lp determine his AOA. These systems require calibration and testing. I do
ubt these folks had time to test and calibrate aircraft systems in flight t
est yet. Un-calibrated equipment often times leads to more cockpit distrac
tions 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=2C Annex E for wing angles/tail plane a
ngles and control throws is not enough. Retract tests are essential to ver
ify gear lock=2C flap position/operation=2C and outrigger lock operates ful
l 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 prim
ed at max angle with only 5 gallons total (the main and reserve side holdin
g 2.5 each across the saddle) in 5 seconds or less. Complete Wt. and Balan
ce and a review of max forward=2C aft and test flight loads and CGs verifie
d on the Wt and Bal form. (I normally will fly with a minimum of 10 gallon
s 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=2C and if there is a
cockpit smoke situation=2C battery off=2C 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 re
d 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=2C Transponder is often required=2C ELT operational=2C (I turn AOA and
Autopilots off).
The night before=2C I chair fly and prepare for the flight. I go over airc
raft systems=2C test parameters=2C panel layout and specifics of complex el
ectrical systems.
Flight one is 15 minutes to check for runs drips and errors. (Immediate ac
celeration to 75 and climb at 90.) (Normally I can fly one of our planes ha
nds off=2C feet only=2C half way down the 4000 foot strip above 50 feet.) C
limb to 2500 feet or so and check the trim and rig from 70 to 100 Knots. R
eturn to the pattern=2C 80 on downwind=2C no slower than 75 in the turns=2C
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 foun
d abnormal.
Flight two expands the envelope to check engine climb temps and performance
. Check CS prop operation=2C and climb 3 mistakes high and do A/S verifica
tion=2C stalls=2C falls and pitch and roll stability. Typically our engine
s are flawless so it is only a 45 minute flight. If all goes well and we h
ave good stall characteristics=2C go back and review the flight. (I have
needed stall strips on the root to get a good early burble feel prior to st
all.
Once I am convinced the pilot (who has normally flown in my aircraft for ab
out 5 hours and is very current in other types) is ready=2C I prebrief with
him and hand him the keys for a test hop.
However=2C 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 thi
s. 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 t
o knock on the test pilots door and explain her husband is dead=2C and ther
e was nothing that you could have done to make the aircraft safer.)
Typically in the flight phase we go out dual and do stalls=2C slow flight
=2C advance handling at minimum speeds and ascertain if the pilot is comfor
table=2C the stalls are predictable and easily recognized. ( I am the tech
nical observer who is verifying airspeeds=2C pitch angles=2C stall buffet
=2C system operation and calibration while the client flies.) This is wher
e the AOA=2C Autopilot etc. gets calibrated or rung out.
Frankly=2C 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 win
g aircraft are different). That said=2C after the 3rd 300 mile leg in 90F
degree weather=2C sometimes it is nice to have "Bitching Betty" remind me t
hat I am not paying attention. Fatigue and complacency do set in to us all
. If one adds my vortex generators for STOL capability=2C watch your speed
as the aircraft handles so well down to 50 Knots clean=2C you could be fal
ling with style and not know it unless looking at the airspeed. Here is wh
ere an AOA=2C Airspeed Warner like the Europa Stall indicator=2C 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 a
ccidents and my own experiences. Then when appropriate=2C pass on the har
d learned lessons to those who may benefit. Regards to all=2CBud
Date: Sun=2C 11 May 2014 23:03:53 +0100
From: grahamsingleton@btinternet.com
Subject: Europa-List: Re: Europa-List: Re: Europa crash in L=C3=BCbeck/Germ
any
Graeme
I was refering to the Classic Europa wing. The section has a slight bump ju
st
under the LE which is very easily sanded off. The nose radius is also quite
small=2C
again easy to sand off even with a sheet of fine abrasive round the LE.Accu
rate
templates are essential and the plans version isn't accurate enough for the
se 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=2C 11 May 2014=2C 18:57
Subject: Europa-List: Re: Europa crash in L=C3=BCbeck/Germany
Interesting to hear that you can fly with a flap down=3B but for me a lot i
s going on just after take off=2C watching the gauges=2C the speed the VSI
=2C changing prop pitch=2C unlocking to get the wheel up and pushing the le
aver with the right hand etc - maybe the spring/tension is a bit off if its
first flight=2C I am not sure how I would cope if there were to be a sudde
n roll at that point.
Yep I also value Grahams wisdom and contributions=3B I am just thinking of
the message=2C unintentionally=2C its sending to=0A
current builders. The fact is hundreds have been made by imperfect amateur
s 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
p=3B -Matt Dralle=2C Libution"=0A
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