Today's Message Index:
----------------------
1. 04:08 AM - Re: Coolant leak (Trevpond@aol.com)
2. 06:09 AM - Re: power settings (Karl Heindl)
3. 06:15 AM - Re: power settings (jimpuglise@comcast.net)
4. 07:47 AM - Re: power settings (Karl Heindl)
5. 08:17 AM - Re: Mod 73 - a safer approach (Rick Stockton)
6. 08:47 AM - A question for the group? (Rick Stockton)
7. 09:59 AM - power settings (Remi Guerner)
8. 11:36 AM - Re: A question for the group? (Karl Heindl)
9. 03:40 PM - Re: Flight test data sheets (ALAN YERLY)
10. 03:40 PM - Re: power settings (rampil)
11. 03:55 PM - Re: Coolant leak fix from Kim Prout (Kim Prout)
12. 06:45 PM - Re: power settings (ALAN YERLY)
13. 07:16 PM - Re: power settings (rampil)
14. 08:12 PM - Re: power settings (Garry)
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Subject: | Re: Coolant leak |
Hi Paul,
I had similar problems with my aircraft - sorted it with Nev's help by
fitting double jubilee clips on radiator connections.
regards
Trev Pond
G-LINN
Message 2
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do not archive Hi Bud=2C Your notes are extremely useful and I would like
to print them off. But for some reason your emails are double the width of
everyone else's and I am scrolling left and right for each line and cannot
make to fit on a page=2C even in landscape format. Is there a simple way of
reformatting it ?
Cheers=2C Karl
From: budyerly@msn.comTo: europa-list@matronics.comSubject: Re: Europa-List
: power settingsDate: Sat=2C 27 Dec 2008 00:01:52 -0500
Happy Holidays=2C
Just to throw my hat in...As I have too much time on my hands today...
Propeller charts=2C ram intake effects=2C cowl mods=2C prop diameters=2C et
c. all affect our aircraft's performance data.
I agree with all of you that the Rotax Engine Manual is lacking to non exis
tent for use in accurate data measurement for cruise. God only knows what
the propeller efficiency is. And since we design off the engine charts=2C
which in no way reflect actual engine installation effects=2C we are best e
quipped=2C as experimenters=2C to follow the age old technique of recorded
pilot data from a specific test aircraft. Namely=2C Yours.
When I get a chance to flight test an aircraft for a week or so=2C I log as
much data as the owner lets me. Unfortunately I don't get to do this very
often as it is quite time consuming and I leave it to the customer to cons
ider how much he wants me to fly when he has a perfectly safe airplane. Fr
ankly=2C most of you want to go fly=2C and all this data seems dumb. If yo
u are happy cruising at 5500-6500 ft=2C 5000 rpm=2C 26" MP=2C and 4.5 gph
=2C going as fast as the ground speed says=2C don't read on. I have a "sim
ple chart" done up in my flight test book to jog my memory so I don't do so
mething dumb like just fly around during the customers 40 hour fly off. Af
ter all=2C test flying is supposed to be work.
I've read your posts and you guys are somewhat correct=2C but talking a dif
ferent language. What is needed=2C in my opinion=2C is a chart/table=2C de
rived from data that is painfully boring to fill out and takes about 5 test
flights. This is the data that then translates to Horsepower vs Speed cha
rts to be translated into best cruise and climb performance suited to your
aircraft. I've partially tested RV's (4 and 6) and fully tested a Zenith (
Subaru E85) extensively as well as two Europa's=2C one a with a warp drive
fixed prop the other with an Airmaster using variations of these data chart
s=2C and you can tweak your plane to get the most performance out of it by
proper testing. It will also make the Rotax engine power curves start to m
ake sense.
Here's the gist:
Cruise data chart for Aircraft make model=2C engine type=2C prop type at a
specified gross weight:
Density Altitude=2C RPM=2C MP=2C IAS=2C TAS=2C Fuel Flow=2C additional data
(see note)
Sea Level
2500
5000
7500
10=2C000
Note: Log for your use items such as=3B Oil T/P=2C Cyl. Head=2C Coolant =2C
EGT etc. so you can track any future trends.
But wait=2C there's more. Why climb up to cruise and not record climb also
.
Climb Data for Aircraft make model=2C engine type=2C prop type=2C Gross Wei
ght:
Climb Speed Start Climb=2C End Climb Duration=2C Power Setting RPM=2C MP
Start Temp=2C PA=2C DA Fuel Flow (See Note)
75 knots 100 1000 58sec 5700 38"
15C=2C100=2C110 7.5
85Knots 100 1000 65 5700 38.3
15C=2C 100=2C110 7.5
etc.
2500 2500 5000 200sec 5500 35
11C 2500=2C 2750 7.3
Note: Great time to log cyl head and coolant readings.
I try to climb at 75=2C 85. 95=2C and 105 Knots just to see the difference
in climb and rates of cooling. Why these numbers? They are easy to see an
d chart.
But wait there's even more=2C so go back to chart one and do the cruise fro
m different power settings. Get close to the Rotax/Jabiru numbers such as
55%=2C 65%=2C 75%=2C and max continuous power settings. The data for the 9
12/912S/Jabiru will vary due to intake variations=2C and be pretty consiste
nt for the 914.
Don't forget it is all done at a specific gross weight so in-flight refuel
to get the data as accurate as possible or do it over 5 flights.
Record the data as Dykins did in the Europa books (good reading by the way)
and then through some analysis=2C you will have useable data for creating
charts which can be condensed down to be used in your Pilot Handbook as an
attached performance page.
I copied the idea for the performance info from Dykins=2C Chris Heinz=2C EA
A=2C and anyone else who made a performance data sheet/manual or checklist
and of course my "Airplane Aerodynamics" textbook by Dommasch=2C Sherby and
Connolly. The data I have acquired so far will be to put together in the
future for proper HP/Speed charts for the Europa and for my Classic Europa.
The data points give me the ability to construct charts for climb=2C crui
se planning and emergency procedures=2C such as max range=2C divert and gli
de. Each of our planes is different=2C so our data will be slightly differ
ent=2C so don't expect one plane's data to exactly reflect another's=2C unl
ess they were built on an assembly line.
I am attaching two excel files=2C one of my old blank performance data chec
klists and the other=2C my personal Europa checklist (they are old versions
from a memory stick found at home=2C but good enough to show the performan
ce page I made in my checklist). It is this type data analysis that preven
ts pilots from over-boosting their 912/914/Airmaster combination and dumpin
g gas out of the tailpipe because they blindly set a power setting and neve
r plotted the A/S vs Power curves to get max range computations... Guys al
ways want more gas. Slowing down a few knots can get you 100 miles farther
per leg or even more if you slow down to around 90-95 KIAS. You can even
plot accurate charts for headwind / tailwind effects. Another way is to jus
t figure your miles per gallon to get your best cruising power settings for
max range. I see many folks getting 20 mpg instead of 28 mpg. It's just
data=2C and you have the power to analyze it to get your desired informatio
n.
The attached checklists were made for my use and are not a replacement for
factory manuals or formal flight test manuals. Their use is for late in th
e test flight phase when all the bugs have been worked out. Data accumulat
ion requires extensive preflight ground run throughs a.k.a. chair flying=2C
and thorough preflight planning so as not to get your head down=2C when yo
u should be flying. Data doesn't kill you=2C it's the ground and other air
planes. My checklists are from my personal random thoughts and experiences
(scary). Use the company pilot handbook as it is the best policy=2C then
add the performance data you acquired to it just as you did for your weight
and balance.
So... If you are looking for something to do=2C go out and get some formal
ized data. After landing=2C analyze the data=2C plan how to get more data
when flying to the next fly-in breakfast and then over time=2C adjust your
normal climb/cruise operations based on the data to suit your flying needs.
If you feel like sharing=2C put it on the web. If you don't know what t
o do with the data=2C send it to me and I will try break it down for you.
Enjoy the holidays=2C
PS=2C I still haven't shut down a perfectly good engine to get glide data..
.Too many dependents or I'm getting too old for the adventure. Go figure.
Bud
Custom Flight Creations
----- Original Message -----
From: Remi Guerner
Sent: Friday=2C December 26=2C 2008 3:52 PM
Subject: Europa-List: power settings
Ira=2C
I disagree with your assertion that altitude is not needed in your table. A
given setting=2C i.e. 5000 rpm and 22" will give you more power at 8000 ft
than at 1000 ft. because the temperature being colder at 8000 ft=2C the de
nsity of the air at a given manifold pressure is higher.
As an exemple the following power settings are extracted from the Cirrus SR
20 Flight Manual:
2000 ft=2C 2500 rpm=2C 23.8"
4000 ft=2C 2500 rpm=2C 22.3"
6000 ft=2C 2500 rpm=2C 21.8"
8000 ft=2C 2500 rpm=2C 21.2"
All these settings produce the same 65% power on the Continental engine.
So your table as it is today is valid at low altitude only. To be exhaustiv
e=2C it would be necessary to compute one table for each density altitude.
If you are prepared to do that work=2C I am interrested in getting the resu
lts.
Best regards
Remi
>>>>>>>>>>>>The table is engine performance with a constant speed (AirMaste
r) prop.All certificated manufacturers provide a table like mine which show
sthe relationship between throttle=2C selected RPM=2C and power output.Rota
x does not. The graph is useful to select which combinationworks best unde
r specific circumstance=2C particularly when fuel flowand TAS are added to
the table. My data collection is unfinished for thebigger version of the ta
ble. In this version of just engine=2C not airframeperformance=2C density
altitude is unneeded. No matter what densityaltitude=2C throttle sets manif
old pressure=2C and obviously without aturbocharger/supercharger=2C the max
imum MP declines with altitude.The desired rpm is set on your prop control.
Green is the usual operating range=2C the other colors are not important
here.Example: 75% power is obtained at 27.5" and 4800 rpm or26" and 5000 o
r 24" and 5500 rpm. The "standard" cruise settingon Continental or Lycomin
gs of 25 squared (or 2500 rpm @ prop at25" MP) doesn't work out for Rotax b
ecause 2500 rpm would be over6000 engine rpm=2C but by extrapolation would
be over 80% power.Or=2C if you set your prop to 5000 rpm for cruise=2C the
n you get 75% at26" (only possible up 4000' DA)=2C and 65% at 23" MAP.While
there are small inaccuracies due my simple model of the Ottocycle=2C so fa
r as I know=2C this table I created is the only publishedattempt to provide
guidance for 912s drivers with a constant speedprop<<<<<<<<<<<<
href="http://www.matronics.com/contribution">http://www.matronics.com/chr
ef="http://www.matronics.com/Navigator?Europa-List">http://www.matronhref
="http://forums.matronics.com">http://forums.matronics.com
Message 3
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Subject: | Re: power settings |
Karl-
No problem with his post here.=C2- Try hilighting the whole thing, copy i
t and paste it into Word.=C2- You can then set the margins as you please
and it will word wrap.
Jim Puglise.
----- Original Message -----
From: "Karl Heindl" <kheindl@msn.com>
Sent: Saturday, December 27, 2008 9:07:27 AM GMT -05:00 US/Canada Eastern
Subject: RE: Europa-List: power settings
=C2-
do not archive
=C2-
Hi Bud,
=C2-
Your notes are extremely useful and I would like to print them off. But for
some reason your emails are double the width of everyone else's and I am s
crolling left and right for each line and cannot make to fit on a page, eve
n in landscape format. Is there a simple way of reformatting it ?
=C2-
Cheers,=C2-=C2-=C2- Karl
From: budyerly@msn.com
Subject: Re: Europa-List: power settings
Happy Holidays,
Just to throw my hat in...As I have too much time on my hands today...
Propeller charts, ram intake effects, cowl mods, prop diameters, etc. all a
ffect our aircraft's performance data.
I agree with all of you that the Rotax Engine Manual is lacking to non exis
tent for use in accurate data measurement for cruise.=C2- God only knows
what the propeller efficiency is.=C2- And since we design off the engine
charts, which in no way reflect actual engine installation effects, we are
best equipped, as experimenters,=C2-to follow the age old technique of re
corded pilot data from a specific test aircraft.=C2- Namely, Yours.=C2-
When I get a chance to flight test an aircraft for a week or so, I log as m
uch data as the owner=C2-lets me.=C2- Unfortunately I don't get to do t
his very often as it is quite time consuming and I leave it to the customer
to=C2-consider how much he wants me to fly when he has a perfectly safe
airplane.=C2- Frankly, most of you want to go fly, and all this data=C2
-seems dumb. =C2-If you are happy cruising at 5500-6500 ft, 5000 rpm, 2
6" MP, and 4.5 gph, going as fast as the ground speed says, don't read on.
=C2- I have a "simple chart" done up in my flight test book to jog my mem
ory so I don't do something dumb like just fly around during the customers
40 hour fly off.=C2- After all, test flying is supposed to be work.
I've read your posts and you guys are=C2-somewhat correct, but talking a
different language.=C2-=C2-What is needed, in my opinion, is a chart/ta
ble, derived from data that is painfully=C2-boring to fill out and takes
about 5 test flights.=C2- This is the data that then translates to Horsep
ower=C2-vs Speed charts to be translated into best=C2-cruise and climb
performance suited to your aircraft.=C2- I've partially tested RV's (4 an
d 6) and fully tested a Zenith (Subaru E85) extensively=C2-as well as two
Europa's, one a with a warp drive fixed prop the other with an Airmaster u
sing variations of these data=C2-charts, and you can tweak your plane to
get the most performance out of it by proper testing.=C2- It will also ma
ke the Rotax engine power curves start to make sense.
Here's the gist:
Cruise data chart for Aircraft make model, engine type, prop type at a spec
ified gross weight:
Density Altitude, RPM, MP, IAS, TAS, Fuel Flow, additional data (see note)
Sea Level
2500
5000
7500
10,000
Note: Log for your use items such as; Oil T/P, Cyl. Head, Coolant , EGT etc
. so you can track any future trends.
But wait, there's more.=C2- Why climb up to cruise and not record climb a
lso.
Climb Data for Aircraft make model, engine type, prop type, Gross Weight:
Climb Speed=C2-Start Climb, End Climb=C2-=C2-=C2-Duration, Power Se
tting=C2-RPM, MP=C2-Start Temp, PA, DA=C2-=C2-=C2-Fuel Flow (See
Note)
75 knots 100=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-1000=C2-=C2
-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-58sec=C2-=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-5700=C2-=C2-=C2-=C2
-=C2-=C2-38"=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2
-=C2-=C2-15C,100,110=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-7.5
85Knots 100=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-1000=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-65=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2
-=C2-5700=C2-=C2-=C2-=C2-38.3=C2-=C2-=C2-=C2-=C2-=C2
-=C2-=C2-=C2-=C2-=C2-=C2-15C, 100,110=C2-=C2-=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-7.5
etc.
=C2-2500=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-2500=C2-=C2-
=C2-=C2-=C2-=C2-=C2-=C2-5000=C2-=C2-=C2-=C2-=C2-=C2
-=C2-=C2-=C2-=C2-=C2-200sec=C2-=C2-=C2-=C2-=C2-=C2-
=C2-=C2-=C2-5500=C2-=C2-=C2-=C2-35=C2-=C2-=C2-=C2-=C2
-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-11C 25
00, 2750=C2-=C2-=C2-=C2-=C2-=C2-=C2-=C2-7.3
Note:=C2- Great time to log cyl head and coolant readings.
I try to climb at 75, 85. 95, and 105 Knots just to see the difference in c
limb and rates of=C2-cooling.=C2- Why these numbers?=C2- They are eas
y to see and chart.=C2-
But wait there's even=C2-more, so=C2-go back to chart one and do the cr
uise from different power settings.=C2- Get close to the Rotax/Jabiru num
bers such as 55%, 65%, 75%, and max continuous power settings.=C2- The da
ta for the 912/912S/Jabiru will vary due to intake variations, and be prett
y consistent for the 914.
Don't forget it is all done at a specific gross weight so in-flight refuel
to get the data as accurate as possible or do it over 5 flights.
Record the data as Dykins did in the Europa books (good reading by the way)
and then through some analysis, you will have useable data for creating ch
arts which can be condensed down to be used in your Pilot Handbook as an at
tached performance page.
I=C2-copied the idea for=C2-the performance info from Dykins, Chris Hei
nz, EAA, and anyone else who made a performance data sheet/manual or checkl
ist and of course my "Airplane Aerodynamics" textbook by Dommasch, Sherby a
nd Connolly.=C2- The data I have=C2-acquired so far will be to put toge
ther in the future for proper HP/Speed charts for the Europa and for my Cla
ssic Europa.=C2- The data points give me the ability to construct charts
for climb, cruise planning and emergency procedures, such as max range, div
ert and glide.=C2- Each of our planes is different, so our data will be s
lightly different, so don't expect one plane's data to exactly reflect anot
her's, unless they=C2-were built on an assembly line.
I=C2-am attaching two excel files, one=C2-of my old blank performance d
ata checklists and the other, my personal Europa checklist (they are old ve
rsions=C2-from a=C2-memory stick found at home, but good enough to=C2
-show the performance page I made in my checklist). =C2-It is this type
data analysis that prevents pilots from over-boosting=C2-their 912/914/A
irmaster combination and dumping gas out of the tailpipe because they blind
ly set a power setting and never=C2-plotted the=C2-A/S vs Power=C2-cu
rves to get max range computations...=C2- Guys always want more gas.=C2
- Slowing down a few knots can get you 100 miles farther per leg or even
=C2-more if you slow down to around 90-95 KIAS.=C2- You can even plot a
ccurate charts=C2-for headwind / tailwind=C2-effects.=C2-Another way
is to just figure your miles per gallon to get your best cruising power set
tings for max range.=C2- I see=C2-many folks getting 20 mpg instead of
28 mpg.=C2- It's just data, and you have the power to=C2-analyze=C2-i
t to get your desired information.
The attached=C2-checklists were made=C2-for my use and are not a replac
ement for factory manuals or formal flight test manuals.=C2- Their use is
for late in the test flight phase when all the bugs have been worked out.
=C2- Data accumulation requires extensive preflight ground run throughs a
.k.a. chair flying, and thorough preflight planning so as not to get your h
ead down, when you should be flying.=C2- Data doesn't kill you, it's the
ground and other airplanes.=C2- My checklists are=C2-from my personal r
andom thoughts and experiences (scary).=C2- Use the company pilot handboo
k=C2-as it is the best policy, then add the performance data you acquired
to it just as you did for your weight and balance.
So...=C2- If you are looking for something to do, go out and get some for
malized data.=C2- After landing, analyze the data, plan how to get more d
ata=C2-when flying to the next fly-in breakfast and then over time, adjus
t your normal climb/cruise operations based on the data to suit your flying
needs.=C2-=C2-=C2-If you feel like sharing, put it on the web.=C2-
If you=C2-don't know what to do with the data, send it to me and I will
try break it down for you.=C2-
Enjoy the holidays,
PS, I still haven't shut down a perfectly good engine to get glide data...T
oo many dependents or I'm getting too old for the adventure.=C2- Go figur
e.
Bud
Custom Flight Creations
----- Original Message -----
From: Remi Guerner
Sent: Friday, December 26, 2008 3:52 PM
Subject: Europa-List: power settings
Ira,
I disagree with your assertion that altitude is not needed in your table. A
given setting, i.e. 5000 rpm and 22" will=C2-give you more=C2-power at
8000 ft than at 1000 ft. because the temperature being colder at 8000 ft,
the density of the air at a given manifold pressure is higher.
As an exemple the following power settings=C2-are extracted from the Cirr
us SR20 Flight Manual:=C2-=C2-
2000 ft, 2500 rpm, 23.8"
4000 ft, 2500 rpm, 22.3"
6000 ft, 2500 rpm, 21.8"
8000 ft, 2500 rpm, 21.2"
All these settings produce the same 65% power on the Continental engine.
So your table as it is today is valid at low altitude only. To be exhaustiv
e, it would be necessary to compute one table for each density altitude. If
you are prepared to do that work, I am interrested in getting the results.
Best regards
Remi
>>>>>>>>>>>>The table is engine performance with a constant speed (AirMaste
r) prop.
All certificated manufacturers provide a table like mine which shows
the relationship between throttle, selected RPM, and power output.
Rotax does not.=C2- The graph is useful to select which combination
works best under specific circumstance, particularly when fuel flow
and TAS are added to the table. My data collection is unfinished for the
bigger version of the table.=C2- In this version of just engine, not airf
rame
performance, density altitude is unneeded. No matter what density
altitude, throttle sets manifold pressure, and obviously without a
turbocharger/supercharger, the maximum MP declines with altitude.
The desired rpm is set on your prop control.=C2- Green is the usual
operating range, the other colors are not important here.
Example: 75% power is obtained at=C2- 27.5" and 4800 rpm or
26" and 5000 or 24" and 5500 rpm.=C2- The "standard" cruise setting
on Continental or Lycomings of 25 squared (or 2500 rpm @ prop at
25" MP) doesn't work out for Rotax because 2500 rpm would be over
6000 engine rpm,=C2- but by extrapolation would be over 80% power.
Or, if you set your prop to 5000 rpm for cruise, then you get 75% at
26" (only possible up 4000' DA), and 65% at 23" MAP.
While there are small inaccuracies due my simple model of the Otto
cycle, so far as I know, this table I created is the only published
attempt to provide guidance for 912s drivers with a constant speed
prop<<<<<<<<<<<<
href="http://www.matronics.com/contribution">http://www.matronics.com/chr
ef="http://www.matronics.com/Navigator?Europa-List">http://www.matronhref
=====
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|
Thank you Jim. I am just curious as to why it only happens in this one case
. I use Microsoft hotmail.
do not archive
pa-list@matronics.comSubject: Re: Europa-List: power settings
Karl-
No problem with his post here. Try hilighting the whole thing=2C copy it a
nd paste it into Word. You can then set the margins as you please and it w
ill word wrap.
Jim Puglise.
----- Original Message -----From: "Karl Heindl" <kheindl@msn.com>To: europa
-list@matronics.comSent: Saturday=2C December 27=2C 2008 9:07:27 AM GMT -05
:00 US/Canada EasternSubject: RE: Europa-List: power settings
do not archive Hi Bud=2C Your notes are extremely useful and I would like
to print them off. But for some reason your emails are double the width of
everyone else's and I am scrolling left and right for each line and cannot
make to fit on a page=2C even in landscape format. Is there a simple way of
reformatting it ? Cheers=2C Karl
From: budyerly@msn.comTo: europa-list@matronics.comSubject: Re: Europa-List
: power settingsDate: Sat=2C 27 Dec 2008 00:01:52 -0500
Happy Holidays=2C
Just to throw my hat in...As I have too much time on my hands today...
Propeller charts=2C ram intake effects=2C cowl mods=2C prop diameters=2C et
c. all affect our aircraft's performance data.
I agree with all of you that the Rotax Engine Manual is lacking to non exis
tent for use in accurate data measurement for cruise. God only knows what
the propeller efficiency is. And since we design off the engine charts=2C
which in no way reflect actual engine installation effects=2C we are best e
quipped=2C as experimenters=2C to follow the age old technique of recorded
pilot data from a specific test aircraft. Namely=2C Yours.
When I get a chance to flight test an aircraft for a week or so=2C I log as
much data as the owner lets me. Unfortunately I don't get to do this very
often as it is quite time consuming and I leave it to the customer to cons
ider how much he wants me to fly when he has a perfectly safe airplane. Fr
ankly=2C most of you want to go fly=2C and all this data seems dumb. If yo
u are happy cruising at 5500-6500 ft=2C 5000 rpm=2C 26" MP=2C and 4.5 gph
=2C going as fast as the ground speed says=2C don't read on. I have a "sim
ple chart" done up in my flight test book to jog my memory so I don't do so
mething dumb like just fly around during the customers 40 hour fly off. Af
ter all=2C test flying is supposed to be work.
I've read your posts and you guys are somewhat correct=2C but talking a dif
ferent language. What is needed=2C in my opinion=2C is a chart/table=2C de
rived from data that is painfully boring to fill out and takes about 5 test
flights. This is the data that then translates to Horsepower vs Speed cha
rts to be translated into best cruise and climb performance suited to your
aircraft. I've partially tested RV's (4 and 6) and fully tested a Zenith (
Subaru E85) extensively as well as two Europa's=2C one a with a warp drive
fixed prop the other with an Airmaster using variations of these data chart
s=2C and you can tweak your plane to get the most performance out of it by
proper testing. It will also make the Rotax engine power curves start to m
ake sense.
Here's the gist:
Cruise data chart for Aircraft make model=2C engine type=2C prop type at a
specified gross weight:
Density Altitude=2C RPM=2C MP=2C IAS=2C TAS=2C Fuel Flow=2C additional data
(see note)
Sea Level
2500
5000
7500
10=2C000
Note: Log for your use items such as=3B Oil T/P=2C Cyl. Head=2C Coolant =2C
EGT etc. so you can track any future trends.
But wait=2C there's more. Why climb up to cruise and not record climb also
.
Climb Data for Aircraft make model=2C engine type=2C prop type=2C Gross Wei
ght:
Climb Speed Start Climb=2C End Climb Duration=2C Power Setting RPM=2C MP
Start Temp=2C PA=2C DA Fuel Flow (See Note)
75 knots 100 1000 58sec 5700 38"
15C=2C100=2C110 7.5
85Knots 100 1000 65 5700 38.3
15C=2C 100=2C110 7.5
etc.
2500 2500 5000 200sec 5500 35
11C 2500=2C 2750 7.3
Note: Great time to log cyl head and coolant readings.
I try to climb at 75=2C 85. 95=2C and 105 Knots just to see the difference
in climb and rates of cooling. Why these numbers? They are easy to see an
d chart.
But wait there's even more=2C so go back to chart one and do the cruise fro
m different power settings. Get close to the Rotax/Jabiru numbers such as
55%=2C 65%=2C 75%=2C and max continuous power settings. The data for the 9
12/912S/Jabiru will vary due to intake variations=2C and be pretty consiste
nt for the 914.
Don't forget it is all done at a specific gross weight so in-flight refuel
to get the data as accurate as possible or do it over 5 flights.
Record the data as Dykins did in the Europa books (good reading by the way)
and then through some analysis=2C you will have useable data for creating
charts which can be condensed down to be used in your Pilot Handbook as an
attached performance page.
I copied the idea for the performance info from Dykins=2C Chris Heinz=2C EA
A=2C and anyone else who made a performance data sheet/manual or checklist
and of course my "Airplane Aerodynamics" textbook by Dommasch=2C Sherby and
Connolly. The data I have acquired so far will be to put together in the
future for proper HP/Speed charts for the Europa and for my Classic Europa.
The data points give me the ability to construct charts for climb=2C crui
se planning and emergency procedures=2C such as max range=2C divert and gli
de. Each of our planes is different=2C so our data will be slightly differ
ent=2C so don't expect one plane's data to exactly reflect another's=2C unl
ess they were built on an assembly line.
I am attaching two excel files=2C one of my old blank performance data chec
klists and the other=2C my personal Europa checklist (they are old versions
from a memory stick found at home=2C but good enough to show the performan
ce page I made in my checklist). It is this type data analysis that preven
ts pilots from over-boosting their 912/914/Airmaster combination and dumpin
g gas out of the tailpipe because they blindly set a power setting and neve
r plotted the A/S vs Power curves to get max range computations... Guys al
ways want more gas. Slowing down a few knots can get you 100 miles farther
per leg or even more if you slow down to around 90-95 KIAS. You can even
plot accurate charts for headwind / tailwind effects. Another way is to jus
t figure your miles per gallon to get your best cruising power settings for
max range. I see many folks getting 20 mpg instead of 28 mpg. It's just
data=2C and you have the power to analyze it to get your desired informatio
n.
The attached checklists were made for my use and are not a replacement for
factory manuals or formal flight test manuals. Their use is for late in th
e test flight phase when all the bugs have been worked out. Data accumulat
ion requires extensive preflight ground run throughs a.k.a. chair flying=2C
and thorough preflight planning so as not to get your head down=2C when yo
u should be flying. Data doesn't kill you=2C it's the ground and other air
planes. My checklists are from my personal random thoughts and experiences
(scary). Use the company pilot handbook as it is the best policy=2C then
add the performance data you acquired to it just as you did for your weight
and balance.
So... If you are looking for something to do=2C go out and get some formal
ized data. After landing=2C analyze the data=2C plan how to get more data
when flying to the next fly-in breakfast and then over time=2C adjust your
normal climb/cruise operations based on the data to suit your flying needs.
If you feel like sharing=2C put it on the web. If you don't know what t
o do with the data=2C send it to me and I will try break it down for you.
Enjoy the holidays=2C
PS=2C I still haven't shut down a perfectly good engine to get glide data..
.Too many dependents or I'm getting too old for the adventure. Go figure.
Bud
Custom Flight Creations
----- Original Message -----
From: Remi Guerner
Sent: Friday=2C December 26=2C 2008 3:52 PM
Subject: Europa-List: power settings
Ira=2C
I disagree with your assertion that altitude is not needed in your table. A
given setting=2C i.e. 5000 rpm and 22" will give you more power at 8000 ft
than at 1000 ft. because the temperature being colder at 8000 ft=2C the de
nsity of the air at a given manifold pressure is higher.
As an exemple the following power settings are extracted from the Cirrus SR
20 Flight Manual:
2000 ft=2C 2500 rpm=2C 23.8"
4000 ft=2C 2500 rpm=2C 22.3"
6000 ft=2C 2500 rpm=2C 21.8"
8000 ft=2C 2500 rpm=2C 21.2"
All these settings produce the same 65% power on the Continental engine.
So your table as it is today is valid at low altitude only. To be exhaustiv
e=2C it would be necessary to compute one table for each density altitude.
If you are prepared to do that work=2C I am interrested in getting the resu
lts.
Best regards
Remi
>>>>>>>>>>>>The table is engine performance with a constant speed (AirMaste
r) prop.All certificated manufacturers provide a table like mine which show
sthe relationship between throttle=2C selected RPM=2C and power output.Rota
x does not. The graph is useful to select which combinationworks best unde
r specific circumstance=2C particularly when fuel flowand TAS are added to
the table. My data collection is unfinished for thebigger version of the ta
ble. In this version of just engine=2C not airframeperformance=2C density
altitude is unneeded. No matter what densityaltitude=2C throttle sets manif
old pressure=2C and obviously without aturbocharger/supercharger=2C the max
imum MP declines with altitude.The desired rpm is set on your prop control.
Green is the usual operating range=2C the other colors are not important
here.Example: 75% power is obtained at 27.5" and 4800 rpm or26" and 5000 o
r 24" and 5500 rpm. The "standard" cruise settingon Continental or Lycomin
gs of 25 squared (or 2500 rpm @ prop at25" MP) doesn't work out for Rotax b
ecause 2500 rpm would be over6000 engine rpm=2C but by extrapolation would
be over 80% power.Or=2C if you set your prop to 5000 rpm for cruise=2C the
n you get 75% at26" (only possible up 4000' DA)=2C and 65% at 23" MAP.While
there are small inaccuracies due my simple model of the Ottocycle=2C so fa
r as I know=2C this table I created is the only publishedattempt to provide
guidance for 912s drivers with a constant speedprop<<<<<<<<<<<<
href="http://www.matronics.com/contribution">http://www.matronics.com/chr
ef="http://www.matronics.com/Navigator?Europa-List">http://www.matronhref
="http://forums.matronics.com">http://forums.matronics.com
blank>http://www.matronics.com/contribution
arget=_blank>http://www.matronics.com/Navigator?Europa-List
p://forums.matronics.com
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Subject: | Mod 73 - a safer approach |
Brad, I was wondering if the mandrel might help me.- After completing MOD
73 without using the torque tube.- I have a build up of restin on the be
aring surface.- I have tried to remove it with some different methods, bu
t so far I have not had a lot of luck.-
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Subject: | A question for the group? |
I am about to cut the top off of my tunnel so that I can place some clamps
in the wheel well area to hold my electrical wiring, fuel hoses and such.
-- I=A2m trying to figure out which is the best a throttle cable or thr
ottle quadrant. -Because of the low valve of the U.S. dollar I=A2m planni
ng on installing the Jibiru 3300.- The prop is still in to be determined.
- I have looked at the pictures in the Europa Owners Gallery and see all
the different ways that mechanic-in-charge has installed them.-
My question is what do you think is the best system: Throttle cable vs Thro
ttle Quadrant for this engine setup and why.-
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Ira,
You misread me. I said that a given combination of MP and RPM gives you
more power at altitude. I am not talking about max full throttle power.
Of course I agree that full throttle power decreases with altitude on
any normally aspirated engine.
Go back to the SR20 exemple: flying at 8000 ft, 2500 rpm and 21.2" MAP
give you 65% power. Now flying at 2000 ft you need 23.8" of MAP to get
the same 65% power at the same 2500 RPM, so obviously if you fly at 2500
rpm and 21.2" MAP at 2000 ft you will get less than 65% power. At 2000
ft the ISA temperature is 11degC while at 8000ft it is -1 degC.
Therefore the density of the air at the same 21.2" pressure is higher at
8000 ft than it is at 2000ft. That is why this 2500 rpm and 21.2" MAP
setting will give you more power at 8000 ft than the same setting at
2000 ft. From my calculation this setting will give 62% power at 2000
ft. That is just the laws of physics and all aircraft engine
manufacturers seems to agree with them.
Cheers
Remi
>>>>>> Your suggestion that a normally aspirated engine
will develop more power at 8000' than at 1000' is quite curious.<<<<<<<
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Subject: | A question for the group? |
Rick=2C
I don't think there is anything special about this engine setup except for
twin-carbs. I have a push/pull throttle with friction control from ACS moun
ted at the bottom of the panel. Just like the Cessnas and Pipers I have flo
wn.
Karl
: Europa-List: A question for the group?To: europa-list@matronics.com
I am about to cut the top off of my tunnel so that I can place some clamps
in the wheel well area to hold my electrical wiring=2C fuel hoses and such.
I=A2m trying to figure out which is the best a throttle cable or throttl
e quadrant. Because of the low valve of the U.S. dollar I=A2m planning on
installing the Jibiru 3300. The prop is still in to be determined. I have
looked at the pictures in the Europa Owners Gallery and see all the differ
ent ways that mechanic-in-charge has installed them.
My question is what do you think is the best system: Throttle cable vs Thro
ttle Quadrant for this engine setup and why.
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Subject: | Re: Flight test data sheets |
Everyone,
I am at the shop and resending my current checklist and data cards in
.xls format should you want to review them. The new MS Word makes a
.xlsx which older versions have trouble opening. This should work. I
hope.
Bud Yerly
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Subject: | Re: power settings |
Hi Remi,
Remember how I used that fine old French chemist, Gay-Lussac,
to show that an isobaric drop of 14C gives only a 5% change
in density - scarcely measurable in the performance of a Europa, i.e.,
you would need many test runs to tease the difference from the noise.
It is because that size of temperature change against the background of
standard atmosphere temperatures is quite small in the Kelvin
temperature scale
It's all a matter of magnitude of effect.
So, if it will make you happy, we can say my chart is only accurate
to 5% from MSL to 8000' DA, and it is still a Christmas gift to
Rotax pilots who otherwise have no guidance at all from the factory in
setting a constant speed prop.
Regards,
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=221411#221411
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Subject: | Re: Coolant leak fix from Kim Prout |
Hey Paul! How ya doin there? Anyway, I was reading the thread about the
coolant leak at low temps and I remember a slight problem also. I don't know
what Rotax version you have but the more recent models are supplied with
spring type bands that just go on with pliers. Those are OK. The original
type clamps were just regular jubilee types and could not compensate for
expansion and contraction with temperature changes. I replaced mine with
Oetiker constant tension types that can maintain the proper clamping
pressure no matter what the material and temperature differences. I
eventually replaced the coolant piping from the water pump to the cylinder
heads with a high grade silicone line available from automotive parts
stores.
Check out the Oetiker site, they are worldwide but also have an office in
Mariette Michigan where I was able to contact a sales rep who comped a
series of clamps for my project. I ended up using the series of small clamps
for the fuel system and have never had any leaks there either.
Hope this helps!
kp
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Subject: | Re: power settings |
Ira and Remi,
Great watching your comments.
Curiosity got to me on how both of you stick by your guns so I decided
to review the DA20 manual and stick my nose where it doesn't belong.
You are comparing apples and oranges.
Do not confuse Thrust horsepower and shaft horsepower.
Ref the DA20 manual figure 5.8(b). Max power is the thrust horsepower
available for that specific prop and engine combination cross referenced
to the altitude, temperature vs the TAS etc...This clearly shows Ira's
point that the shaft horsepower of the engine, as the altitude is
increased, drops off. At sea level the engine prop combination produces
130 ktas, but follow the standard day line up to 6000 feet and the max
power the engine is capable of is 75% and yields 121ktas. Use the
dotted line example and then look at as temperature decreases, the
horsepower increases at a constant altitude, resulting in an increase in
TAS because of an increase in shaft horsepower due to an increase in air
density. Shaft horsepower is directly proportional to fuel air mass
flow and RPM pumping out the watts of power.
Remi, you are right in saying that you get more power, but the real
answer is, thrust horse power or THp. THp goes up as speed increases.
>From one of my previous references "Airplane Aerodynamics", I believe
the problem that IRA confuses is he is talking brake horsepower, where
as you are analyzing thrust power required for level unaccellerated
flight. The equation to derive THp is: THp available = TV/550.
Thrust is generated by the relationship of Brake HP times propeller
efficiency. What this shows is there is no Thrust horsepower when
stationary (V=0). Note on the chart referenced above how flat the
power curve line is. But when the speed of the aircraft is considered,
an increase in THp is directly proportional to the speed. Boy this is
boring... Diamond's charts are to make the pilots life easy and are a
brilliant way to get the most from their prop/engine combination. It
really is a plot of HP avail vs HP required points referenced to
altitude and speed. Pretty slick.
Do not confuse MP with horsepower. Let's face it, MP is just the
pressure measured between the valves and throttle body. When combined
with the rpm, fuel flow and prop efficiency you get a number that
equates to the THp measure above. The IO-240 is a fuel injected,
mixture adjustable, ram air induction, engine with a highly refined
Sensenich cruise prop. (If you think Rotax engine data sucks, try to
get the Continental folks to give you the test material. Essentially,
you must show a need, as they don't want it in general distribution.) As
the speed increases at altitude, the Sensenich prop doesn't loose
efficiency as quickly as a normal prop and with the aid of ram induction
you can achieve 65% thrust horsepower at a higher altitude, but your
shaft horsepower is lower. Normally a fixed prop unloads significantly
with speed increase, whereas the Sensenich W69EK-63 is a highly refined
prop tuned to the DA20 airframe and IO-240 engine combination. It has a
target sweet spot of 65 to 75% Thrust Hp from 4000 to 8500 feet at a
nominal 120KTAS while still allowing good takeoff performance. This is
no off the shelf prop. The net result is a prop that can allow you lean
the mixture to compensate for air density so as to use the extra MP from
the ram air and not swing the prop too fast. With a prop pitched like
the one used on the DA20 attached to a Rotax / Bing equipped engine you
would lug the engine down until the plugs fowled shut.
The Europa 912S, with Airmaster prop and non adjustable mixture is a
different animal. It behaves like a normally aspirated engine lowering
its MAP as altitude increases. The fuel injected IO-240 is blessed with
a better intake and fuel metering system. But alas the shaft horsepower
decreases with altitude just as any other plane.
So you're both right.
Better to just plot data for your plane, figure out what works best for
your engine/prop/airframe combination and tweak it like you should.
Every airplane has a sweet spot, you just gotta find it. I prefer to do
it systematically as IRA does, I just prefer a lot more data points to
plot the HP req vs Velocity curves like Dykins does... From these
curves, better understanding of max range, max endurance, miles per
gallon, speed vs economy decisions can be made.
Have a great holiday.
Bud
----- Original Message -----
From: Remi Guerner<mailto:air.guerner@orange.fr>
To: Europa-List Digest Server<mailto:europa-list@matronics.com>
Sent: Saturday, December 27, 2008 12:56 PM
Subject: Europa-List: power settings
Ira,
You misread me. I said that a given combination of MP and RPM gives
you more power at altitude. I am not talking about max full throttle
power. Of course I agree that full throttle power decreases with
altitude on any normally aspirated engine.
Go back to the SR20 exemple: flying at 8000 ft, 2500 rpm and 21.2"
MAP give you 65% power. Now flying at 2000 ft you need 23.8" of MAP to
get the same 65% power at the same 2500 RPM, so obviously if you fly at
2500 rpm and 21.2" MAP at 2000 ft you will get less than 65% power. At
2000 ft the ISA temperature is 11degC while at 8000ft it is -1 degC.
Therefore the density of the air at the same 21.2" pressure is higher at
8000 ft than it is at 2000ft. That is why this 2500 rpm and 21.2" MAP
setting will give you more power at 8000 ft than the same setting at
2000 ft. From my calculation this setting will give 62% power at 2000
ft. That is just the laws of physics and all aircraft engine
manufacturers seems to agree with them.
Cheers
Remi
>>>>>> Your suggestion that a normally aspirated engine
will develop more power at 8000' than at 1000' is quite
curious.<<<<<<<
http://www.matronics.com/contribution<http://www.matronics.com/contributi
on>
http://www.matronics.com/Navigator?Europa-List<http://www.matronics.com/N
avigator?Europa-List>
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Subject: | Re: power settings |
Hi Bud,
Thank you for your illuminating comments!
Always a pleasure to be enlightened by a pro!
See you at SnF I hope.
--------
Ira N224XS
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=221432#221432
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Subject: | Re: power settings |
Ira, Remi and Bud,
You guys are taking all the fun out of flying :-) What happened to the
good old days when we simply "kicked the tires, lit the fires" and went
out flying for fun. All those numbers just confuse me :-)
Garry Stout
----- Original Message -----
From: ALAN YERLY
To: europa-list@matronics.com
Sent: Saturday, December 27, 2008 9:39 PM
Subject: Re: Europa-List: power settings
Ira and Remi,
Great watching your comments.
Curiosity got to me on how both of you stick by your guns so I decided
to review the DA20 manual and stick my nose where it doesn't belong.
You are comparing apples and oranges.
Do not confuse Thrust horsepower and shaft horsepower.
Ref the DA20 manual figure 5.8(b). Max power is the thrust horsepower
available for that specific prop and engine combination cross referenced
to the altitude, temperature vs the TAS etc...This clearly shows Ira's
point that the shaft horsepower of the engine, as the altitude is
increased, drops off. At sea level the engine prop combination produces
130 ktas, but follow the standard day line up to 6000 feet and the max
power the engine is capable of is 75% and yields 121ktas. Use the
dotted line example and then look at as temperature decreases, the
horsepower increases at a constant altitude, resulting in an increase in
TAS because of an increase in shaft horsepower due to an increase in air
density. Shaft horsepower is directly proportional to fuel air mass
flow and RPM pumping out the watts of power.
Remi, you are right in saying that you get more power, but the real
answer is, thrust horse power or THp. THp goes up as speed increases.
>From one of my previous references "Airplane Aerodynamics", I believe
the problem that IRA confuses is he is talking brake horsepower, where
as you are analyzing thrust power required for level unaccellerated
flight. The equation to derive THp is: THp available = TV/550.
Thrust is generated by the relationship of Brake HP times propeller
efficiency. What this shows is there is no Thrust horsepower when
stationary (V=0). Note on the chart referenced above how flat the
power curve line is. But when the speed of the aircraft is considered,
an increase in THp is directly proportional to the speed. Boy this is
boring... Diamond's charts are to make the pilots life easy and are a
brilliant way to get the most from their prop/engine combination. It
really is a plot of HP avail vs HP required points referenced to
altitude and speed. Pretty slick.
Do not confuse MP with horsepower. Let's face it, MP is just the
pressure measured between the valves and throttle body. When combined
with the rpm, fuel flow and prop efficiency you get a number that
equates to the THp measure above. The IO-240 is a fuel injected,
mixture adjustable, ram air induction, engine with a highly refined
Sensenich cruise prop. (If you think Rotax engine data sucks, try to
get the Continental folks to give you the test material. Essentially,
you must show a need, as they don't want it in general distribution.) As
the speed increases at altitude, the Sensenich prop doesn't loose
efficiency as quickly as a normal prop and with the aid of ram induction
you can achieve 65% thrust horsepower at a higher altitude, but your
shaft horsepower is lower. Normally a fixed prop unloads significantly
with speed increase, whereas the Sensenich W69EK-63 is a highly refined
prop tuned to the DA20 airframe and IO-240 engine combination. It has a
target sweet spot of 65 to 75% Thrust Hp from 4000 to 8500 feet at a
nominal 120KTAS while still allowing good takeoff performance. This is
no off the shelf prop. The net result is a prop that can allow you lean
the mixture to compensate for air density so as to use the extra MP from
the ram air and not swing the prop too fast. With a prop pitched like
the one used on the DA20 attached to a Rotax / Bing equipped engine you
would lug the engine down until the plugs fowled shut.
The Europa 912S, with Airmaster prop and non adjustable mixture is a
different animal. It behaves like a normally aspirated engine lowering
its MAP as altitude increases. The fuel injected IO-240 is blessed with
a better intake and fuel metering system. But alas the shaft horsepower
decreases with altitude just as any other plane.
So you're both right.
Better to just plot data for your plane, figure out what works best
for your engine/prop/airframe combination and tweak it like you should.
Every airplane has a sweet spot, you just gotta find it. I prefer to do
it systematically as IRA does, I just prefer a lot more data points to
plot the HP req vs Velocity curves like Dykins does... From these
curves, better understanding of max range, max endurance, miles per
gallon, speed vs economy decisions can be made.
Have a great holiday.
Bud
----- Original Message -----
From: Remi Guerner
To: Europa-List Digest Server
Sent: Saturday, December 27, 2008 12:56 PM
Subject: Europa-List: power settings
Ira,
You misread me. I said that a given combination of MP and RPM gives
you more power at altitude. I am not talking about max full throttle
power. Of course I agree that full throttle power decreases with
altitude on any normally aspirated engine.
Go back to the SR20 exemple: flying at 8000 ft, 2500 rpm and 21.2"
MAP give you 65% power. Now flying at 2000 ft you need 23.8" of MAP to
get the same 65% power at the same 2500 RPM, so obviously if you fly at
2500 rpm and 21.2" MAP at 2000 ft you will get less than 65% power. At
2000 ft the ISA temperature is 11degC while at 8000ft it is -1 degC.
Therefore the density of the air at the same 21.2" pressure is higher at
8000 ft than it is at 2000ft. That is why this 2500 rpm and 21.2" MAP
setting will give you more power at 8000 ft than the same setting at
2000 ft. From my calculation this setting will give 62% power at 2000
ft. That is just the laws of physics and all aircraft engine
manufacturers seems to agree with them.
Cheers
Remi
>>>>>> Your suggestion that a normally aspirated engine
will develop more power at 8000' than at 1000' is quite
curious.<<<<<<<
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