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william(at)wbliss.co.uk
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 Posted: Sun Sep 18, 2016 12:02 am Post subject: 912ULS to 914? |
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Dear All
I am struggling to get out of a 450m grass strip 2 persons and full fuel
(no baggage).
Has anyone got experience of the improvement in take off performance
with the Rotax 914 over the 912ULS?
I expect this has been debated before but I cannot find a way to search
the matronics website for it.
Thanks
William Bliss G-WUFF
Mono Classic XS firewall forwards. 912ULS, Woodcomp SR3000, Smartcontroller
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JonathanMilbank
Joined: 14 Apr 2012
Posts: 395
Location: Aberdeen area
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| Posted: Sun Sep 18, 2016 1:12 am Post subject: Re: 912ULS to 914? |
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Hi William,
I have experience with the 912UL, the 912ULS as now fitted to my aircraft and some time in a friend's Europa with the 914, which I flew for the initial issue of its permit and subsequently.
Subjectively I can assure you that the extra 15 horses in the 914, available for take-off for a short period, are very noticeable and possibly shortening the run by something like 10%.
But I wouldn't want the 914 for my aircraft, partly because the installed weight is 26 lbs heavier and also there are questions in my mind about its reliability.
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davidjoyce(at)doctors.org
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| Posted: Sun Sep 18, 2016 1:44 am Post subject: 912ULS to 914? |
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William, I have never had any trouble operating from a variety of 400m strips with my XS/914/WoodcompSR2000 or SR3000W combination. There is also a considerable benefit if you want to fly at altitude as it gets more efficient the higher you go effectively. As to reliability the older versions had a tendency for the waste gate to stick if you used Avgas in particular, but this was not too serious - it effectively left you with a fixed manifold pressure, and a 30min job in unsticking it. I have not had any other reliability issues with mine in over 1000hrs. Having said all that I am not sure that I wouldn't go for a 915IS if starting again.
Regards, David Joyce, G-XSDJ
On 2016-09-18 08:52, William Bliss wrote: | Quote: | | Quote: | --> Europa-List message posted by: William Bliss <william(at)wbliss.co.uk (william(at)wbliss.co.uk)>
Dear All
I am struggling to get out of a 450m grass strip 2 persons and full fuel (no baggage).
Has anyone got experience of the improvement in take off performance with the Rotax 914 over the 912ULS?
I expect this has been debated before but I cannot find a way to search the matronics website for it.
Thanks
William Bliss G-WUFF
Mono Classic XS firewall forwards. 912ULS, Woodcomp SR3000, Smartcontroller
ttp://www.matronics.com/Navigator?Europa-List
ics.com
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graeme bird
Joined: 15 Jul 2010
Posts: 434
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| Posted: Sun Sep 18, 2016 10:21 am Post subject: Re: 912ULS to 914? |
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I have a similar set up to you and fly from a short strip, I seem to be unstuck in 200 Meters or less, are you sure your prop is setup to go fine enough? Do you have the wide blades?
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_________________
Graeme Bird
kit4 (Wagstaff) TBD
Kit3 G-CLXU (Gregory) mono 914 xs Woodcomp
Kit2 G-PATS - (kesterton) Mono Classic 912 warpdrive
Kit 1 G-UMPY - Mono Classic/XS 912S, Woodcomp G(@)gdbmk.co.uk |
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Remi Guerner
Joined: 14 Dec 2010
Posts: 284
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| Posted: Sun Sep 18, 2016 11:58 pm Post subject: Re: 912ULS to 914? |
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William,
I did just the opposite (replacing my 914 with a 912S) 11 years ago. The difference in take off performance was not very significant except when using high altitude airstrips.
Stay with the more reliable 912S, you will avoid the hassle and higher cost of maintaining the 914.
Remi
F-PGKL
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bobhitchcock(at)icloud.co
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| Posted: Mon Sep 19, 2016 2:24 am Post subject: 912ULS to 914? |
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Hi William
I have had no difficulty with the 912ULS, Woodcomp SR3000. It's a super combination. Agree with the comments of David and Graeme.
Would further add, go back to basics. I have my own folding distance measuring wheel. Get one, they are only £10. I know this sounds really boring but:
MEASURE THE STRIP. Who said it was 450 metres and when?
HOW HIGH IS THE HEDGE YOU ARE CLEARING. Hedges keep growing and that take off and landing run, imperceptibly become more pressured.
HOW STEEP IS THE slope
As well as the usual: wind speed, direction , rain, length of grass, wet/not wet, air temperature et al.
Unless the airfield is licensed treat all the distances as doubtful unless you prove it to yourself.
Regards
Bob
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budyerly(at)msn.com
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| Posted: Sun Sep 25, 2016 4:14 pm Post subject: 912ULS to 914? |
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William and others,
Takeoff performance and cruise performance are significantly different in the 912 ULS and 914 provided we are equipping them both with constant speed props.
A fixed pitch prop on the 914 leaves much performance wasted. Also, an improperly set up constant speed prop can waste performance as well.
If you have a 450m strip, fully loaded at 1370lb. or even 1450 lbs. over gross max takeoff recommended by some in the US, one only needs to look at the engine performance charts to see that without the Rotax turning near 5700 RPM you are not achieving maximum acceleration and climb potential. Conversely, we all know that one’s cruise will be severely impeded with a fixed pitch prop set at 5700 static as the throttle will have to be retarded significantly to prevent an engine over speed as the airspeed is increased. The 912S vs the 914 is 72KW to 85KW respectively at full rated RPM. That is 15% more power delivered by the 914...
Should one set his fixed pitch propeller to only spool up to 5200 RPM maximum static, one can see that the power output of the 912S and 914 are 68KW and 67.5KW respectively. A dead heat.
In my own testing and reading test reports, on many fixed and variable pitch propellers, I have found the following:
The thrust at full 5700RPM does not vary noticeably between any of the blade types at sea level. From Bolly, to Kiev, to Warp Drive, Whirlwind, Sensenich, Woodcomp, GA and on and on when attached to an aircraft with the same length prop and cowl shape. The thrust scales do not lie. Nothing good happens after 67 inches or so on a Rotax (due to torque limits) and the thrust difference of a 64 and 67 on a constant speed prop hub shows no difference on a Europa XS except the 64 inch prop pitches a bit more. The engine just doesn’t have the torque to spin larger props and deliver the performance one has been traditionally. So what is the perceptive difference?
It is dependent on propeller setup, i.e. pitch and the airframe setup. Propellers are driven by torque not HP (high RPM engines require a gearbox to generate the torque and direct drive engines require a long crank arm to generate the torque). As for the prop, the twist, inertia and airfoil shape of a blade in the low speeds we fly (up to 160-170KTAS on the high end to 120 KTAS on the low end) will achieve slight advantages in speeds at higher altitudes and will achieve a faster spin up on takeoff and or better braking on landing than a plain flat Hartzell or Warp Drive Clark Y airfoil prop but very little difference in reality. I will not degenerate into bragging rites as some prop blades are better in some specific areas as two blades and others as three blades at different altitudes and power settings. Each airframe and pilot technique is slightly different but in testing using one aircraft and the same technique and measuring tools, there is just no significant speed or climb difference between blades in low altitude operations if the setup and pilot techniques are the same... You are looking at 100fpm climb and within 8 knots of cruise from sea level to 15,000 MSL. Example: 12AY will do 140-145 at 5500 rpm and 35 inches MP with any blade at 1000MSL much to my surprise. At altitude, the higher cambered lighter props such as the Whirlwind do perform better than a Warp Drive by about 5-10 knots.
For best performance a constant speed prop is essential in a slick airplane like a Europa to take advantage of takeoff, climb and cruise performance potential. A constant speed prop set up for a max RPM of 5750 ground static at zero airspeed and full power is essential for maximum acceleration and best angle of climb, especially important for short field operations. On a short field approach with the prop set to a fine pitch (constant speed prop set for a maximum RPM of 5750 or so, or said another way, the fine pitch limit stop is very fine), allows the prop to act as a brake on landing. Excess thrust in the flare is the last thing you want on a short field landing. Note: I use 5650 as my static RPM as my clients, during training will rapidly advance the throttle during high speed go-arounds or inflight high speed dives and quick throttle operations, and this gives me a cushion to prevent over speeding the engine.
Another note, ground cooling is enhanced by setting the prop to a courser setting while on the ground to improve flow over the cowl and enhance ground cooling... It took a field trip to the airport to convince the guys of this. Old ideas die hard.
The airframe setup is important also.
Many use low tire pressures for softer landing on a trigear or mono wheel. Flat tires resist rolling.
The mono is limited to full flaps on takeoff which slows acceleration.
Rough field nose high attitudes during the initial acceleration phase detract from ideal acceleration potential.
Getting the tail up on a mono improves acceleration potential but very difficult to measure as control inputs are larger...
Rolling the nose gear along on a rough field in a trigear just adds drag but not as much as the aft stick required to hold the nose fully up. Heavy nosed aircraft do not rotate as well and put excessive weight on the nose tire as well. A more aft CG helps get the nose up with less drag from the stabilator angle needed to get the proper attitude and proper acceleration angle which is slightly nose up and nose wheel nearly off the tarmac...
Half flap or about 10-15 degrees of flaps lowers takeoff speed without increasing drag significantly or causing the aircraft to exhibit that old sinking feeling when out of ground effect after liftoff and considerably shortens the takeoff run.
I can routinely get 12AY (Trigear, 914, Airmaster with any blade (Whirlwind, Sensenich, or Warp Drive) off the ground in 200m (600 feet or so) fully loaded without snatching it off. My takeoff roll off grass is about 250m using soft field techniques at a local soggy grass strip. With 12AY equipped with a fixed pitch prop (5200 Static) in LSA testing, the aircraft took nearly 250m to get off the ground on a hard surface being snatched off, and fully loaded was a pig. On a similarly equipped 912S aircraft, I am seeing 250m takeoffs minimum fully loaded on a hard surface also. That is about a 20 % increase in takeoff run. Note: Even the 120 HP Jabiru equipped aircraft with fixed pitch props set at 2650 static can only get off the ground in 350m.
If you want a short takeoff, get a constant speed prop, set it up properly, inflate your tire(s), use half flaps if you can, accelerate tail high (once you have rudder control) if you can, and she’ll come off the ground in 200-250m normally.
Landing is a different story. The prop has to be in fine pitch or you will have excessive thrust on landing roll out. Approach speed is critical. If your plane is controllable at 45 knots in level flight flaps down I would not recommend an approach speed below 55 Knots as power off, the sink rate is high and if in ground effect, the deceleration is at a controllable rate. Fully loaded on approach at 55 requires only a bit of power, and if the power is not reduced prior to the intended landing site, a long float will ensue. Typically if one crosses the threshold of the runway 5 feet in the air at 55 knots, and the power is pulled at the threshold, the float distance can be 300 meters or more. After touchdown roll out is nominally 200m with hard braking and 400 meters using only aerodynamic braking and light wheel braking at the end of run below 30 knots. Of course a soft field will decrease landing roll and increase roll out deceleration rate.
If you have read my posts on my three mistakes rules, I’m afraid your grass strip is a bit short for what I would call normal full gross continuous operations. I prefer to determine my normal runway length as follows: Acceleration to takeoff, get airborne for 3 seconds, decide to abort and land from that point and glide to an intended landing using normal roll out techniques… That is 1000 meters for me or about 3000 feet more or less. Doing the math: 600 feet for takeoff, 3 seconds or 300 feet of climb to 50 feet and push over to approach at 55, an over 50 foot landing approach to touchdown is 1100 feet, plus an additional 1000 foot roll out using light braking for the turn off only. For a real short field operation as you have 1300 feet or 450m or so, you barely can stop if you abort at 45 knots or minimum takeoff speed and stop by the fence.
Engine choice is personal. Like many of us, I have a very old 914 with the 1000 hour TBO and endured constant minor problems. Every SB applies to my engine. These were design equipment problems and properly maintained, the engine still delivers excellent performance. What has it cost me: A stator, fuel pump, both carbs, and starter replacement, rebuild of my turbo, and repair of the turbo bracket, new hoses, and required education on carb and TCU maintenance and service training. What have I gotten in return, 140-150 knot plus cruise performance at 10,000 feet plus 700-800 fpm climb all the way to 10,000 ft. I never fear a hot day high density altitude takeoff and I spit on carb icing and shock cooling.
The early 912S have had the following: Rough starting, requiring new or modified ignitions, exhaust failures due to harmonic vibrations and that ugly shaking on start and stop, cracked engine blocks, carb heating concerns, stator problems, starter cranking problems, and carb problems also. They do not perform well above 7500 feet due to poor leaning and significant power loss due to altitude is evident.
The brand new engines of both 914 and 912S are much better engines. Much has been learned and incorporated in the last 20 years. The 912iS is not very maintainable in the field due to its proprietary electronics, but it performs superb in comparison to the 912S in economy at cruise. No difference on takeoff performance at sea level to speak of, but better performance at higher takeoff density altitudes...
Bottom line:
If you want good takeoff, climb and cruising performance, get a constant speed with either engine. Research maintenance problems and servicing for the prop of choice. If you are concerned about high altitude operations, get a 914. If you just intend to fly at lower altitude and short hops, a 912S is an excellent value. Even equipped with a fixed pitch prop, it is a nice $100 hamburger cruiser to join your Light Sport buddies at a nearby airport. I prefer high and fast in my area of operations where I need to get to 10,000 feet to clear clouds, and find some cool air and a comfortable range of 300nm. Cruise efficiency is at my choice, from 25-35anmpg (air nautical miles per US gallons) depending on power setting.
Full disclosure, I am a dealer for Airmaster and somewhat predujudiced after 10 years of replacing other brands here in the US.
See my website (www.customflightcreations.com) and click on the techniques section on many topics from cooling to maintenance as well as performance testing and an article on choosing the right propeller options for your aircraft. This section works for other brands of props as well (not the Ivo as friends don’t let friends fly with an Ivo) MT, Airmaster, Woodcomp are all very close in performance but differ in weight, maintenance and operational problems such as time to mandatory overhaul and servicing requirements, corrosion and rot problems, blade wear due to weather and foreign object damage, component life limits, finish problems (peeling paint and cracks), controller operations, failure rates, factory/dealer assistance and availability, finding an English speaking service rep, etc..
An airplane is 20,000 compromises flying in close formation, the choices are yours. Choose wisely.
Best Regards,
Bud Yerly
Custom Flight Creations, Inc.
US Europa and Airmaster Dealer
www.customflightcreations.com
Sent from Mail for Windows 10
From: William Bliss (william(at)wbliss.co.uk)
Sent: Sunday, September 18, 2016 3:58 AM
To: europa-list(at)matronics.com (europa-list(at)matronics.com)
Subject: 912ULS to 914?
--> Europa-List message posted by: William Bliss <william(at)wbliss.co.uk>
Dear All
I am struggling to get out of a 450m grass strip 2 persons and full fuel
(no baggage).
Has anyone got experience of the improvement in take off performance
with the Rotax 914 over the 912ULS?
I expect this has been debated before but I cannot find a way to search
the matronics website for it.
Thanks
William Bliss G-WUFF
Mono Classic XS firewall forwards. 912ULS, Woodcomp SR3000, Smartcontroller
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davidjoyce(at)doctors.org
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| Posted: Mon Sep 26, 2016 12:23 am Post subject: 912ULS to 914? |
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Wow! If there were a Nobel prize for Matronics contributions, that would be a leading contender! David Joyce, GXSDJ
On 2016-09-26 01:10, Bud Yerly wrote: | Quote: |
William and others,
Takeoff performance and cruise performance are significantly different in the 912 ULS and 914 provided we are equipping them both with constant speed props.
A fixed pitch prop on the 914 leaves much performance wasted. Also, an improperly set up constant speed prop can waste performance as well.
If you have a 450m strip, fully loaded at 1370lb. or even 1450 lbs. over gross max takeoff recommended by some in the US, one only needs to look at the engine performance charts to see that without the Rotax turning near 5700 RPM you are not achieving maximum acceleration and climb potential. Conversely, we all know that one's cruise will be severely impeded with a fixed pitch prop set at 5700 static as the throttle will have to be retarded significantly to prevent an engine over speed as the airspeed is increased. The 912S vs the 914 is 72KW to 85KW respectively at full rated RPM. That is 15% more power delivered by the 914...
Should one set his fixed pitch propeller to only spool up to 5200 RPM maximum static, one can see that the power output of the 912S and 914 are 68KW and 67.5KW respectively. A dead heat.
In my own testing and reading test reports, on many fixed and variable pitch propellers, I have found the following:
The thrust at full 5700RPM does not vary noticeably between any of the blade types at sea level. From Bolly, to Kiev, to Warp Drive, Whirlwind, Sensenich, Woodcomp, GA and on and on when attached to an aircraft with the same length prop and cowl shape. The thrust scales do not lie. Nothing good happens after 67 inches or so on a Rotax (due to torque limits) and the thrust difference of a 64 and 67 on a constant speed prop hub shows no difference on a Europa XS except the 64 inch prop pitches a bit more. The engine just doesn't have the torque to spin larger props and deliver the performance one has been traditionally. So what is the perceptive difference?
It is dependent on propeller setup, i.e. pitch and the airframe setup. Propellers are driven by torque not HP (high RPM engines require a gearbox to generate the torque and direct drive engines require a long crank arm to generate the torque). As for the prop, the twist, inertia and airfoil shape of a blade in the low speeds we fly (up to 160-170KTAS on the high end to 120 KTAS on the low end) will achieve slight advantages in speeds at higher altitudes and will achieve a faster spin up on takeoff and or better braking on landing than a plain flat Hartzell or Warp Drive Clark Y airfoil prop but very little difference in reality. I will not degenerate into bragging rites as some prop blades are better in some specific areas as two blades and others as three blades at different altitudes and power settings. Each airframe and pilot technique is slightly different but in testing using one aircraft and the same technique and measuring tools, there is just no significant speed or climb difference between blades in low altitude operations if the setup and pilot techniques are the same... You are looking at 100fpm climb and within 8 knots of cruise from sea level to 15,000 MSL. Example: 12AY will do 140-145 at 5500 rpm and 35 inches MP with any blade at 1000MSL much to my surprise. At altitude, the higher cambered lighter props such as the Whirlwind do perform better than a Warp Drive by about 5-10 knots.
For best performance a constant speed prop is essential in a slick airplane like a Europa to take advantage of takeoff, climb and cruise performance potential. A constant speed prop set up for a max RPM of 5750 ground static at zero airspeed and full power is essential for maximum acceleration and best angle of climb, especially important for short field operations. On a short field approach with the prop set to a fine pitch (constant speed prop set for a maximum RPM of 5750 or so, or said another way, the fine pitch limit stop is very fine), allows the prop to act as a brake on landing. Excess thrust in the flare is the last thing you want on a short field landing. Note: I use 5650 as my static RPM as my clients, during training will rapidly advance the throttle during high speed go-arounds or inflight high speed dives and quick throttle operations, and this gives me a cushion to prevent over speeding the engine.
Another note, ground cooling is enhanced by setting the prop to a courser setting while on the ground to improve flow over the cowl and enhance ground cooling... It took a field trip to the airport to convince the guys of this. Old ideas die hard.
The airframe setup is important also.
Many use low tire pressures for softer landing on a trigear or mono wheel. Flat tires resist rolling.
The mono is limited to full flaps on takeoff which slows acceleration.
Rough field nose high attitudes during the initial acceleration phase detract from ideal acceleration potential.
Getting the tail up on a mono improves acceleration potential but very difficult to measure as control inputs are larger...
Rolling the nose gear along on a rough field in a trigear just adds drag but not as much as the aft stick required to hold the nose fully up. Heavy nosed aircraft do not rotate as well and put excessive weight on the nose tire as well. A more aft CG helps get the nose up with less drag from the stabilator angle needed to get the proper attitude and proper acceleration angle which is slightly nose up and nose wheel nearly off the tarmac...
Half flap or about 10-15 degrees of flaps lowers takeoff speed without increasing drag significantly or causing the aircraft to exhibit that old sinking feeling when out of ground effect after liftoff and considerably shortens the takeoff run.
I can routinely get 12AY (Trigear, 914, Airmaster with any blade (Whirlwind, Sensenich, or Warp Drive) off the ground in 200m (600 feet or so) fully loaded without snatching it off. My takeoff roll off grass is about 250m using soft field techniques at a local soggy grass strip. With 12AY equipped with a fixed pitch prop (5200 Static) in LSA testing, the aircraft took nearly 250m to get off the ground on a hard surface being snatched off, and fully loaded was a pig. On a similarly equipped 912S aircraft, I am seeing 250m takeoffs minimum fully loaded on a hard surface also. That is about a 20 % increase in takeoff run. Note: Even the 120 HP Jabiru equipped aircraft with fixed pitch props set at 2650 static can only get off the ground in 350m.
If you want a short takeoff, get a constant speed prop, set it up properly, inflate your tire(s), use half flaps if you can, accelerate tail high (once you have rudder control) if you can, and she'll come off the ground in 200-250m normally.
Landing is a different story. The prop has to be in fine pitch or you will have excessive thrust on landing roll out. Approach speed is critical. If your plane is controllable at 45 knots in level flight flaps down I would not recommend an approach speed below 55 Knots as power off, the sink rate is high and if in ground effect, the deceleration is at a controllable rate. Fully loaded on approach at 55 requires only a bit of power, and if the power is not reduced prior to the intended landing site, a long float will ensue. Typically if one crosses the threshold of the runway 5 feet in the air at 55 knots, and the power is pulled at the threshold, the float distance can be 300 meters or more. After touchdown roll out is nominally 200m with hard braking and 400 meters using only aerodynamic braking and light wheel braking at the end of run below 30 knots. Of course a soft field will decrease landing roll and increase roll out deceleration rate.
If you have read my posts on my three mistakes rules, I'm afraid your grass strip is a bit short for what I would call normal full gross continuous operations. I prefer to determine my normal runway length as follows: Acceleration to takeoff, get airborne for 3 seconds, decide to abort and land from that point and glide to an intended landing using normal roll out techniques... That is 1000 meters for me or about 3000 feet more or less. Doing the math: 600 feet for takeoff, 3 seconds or 300 feet of climb to 50 feet and push over to approach at 55, an over 50 foot landing approach to touchdown is 1100 feet, plus an additional 1000 foot roll out using light braking for the turn off only. For a real short field operation as you have 1300 feet or 450m or so, you barely can stop if you abort at 45 knots or minimum takeoff speed and stop by the fence.
Engine choice is personal. Like many of us, I have a very old 914 with the 1000 hour TBO and endured constant minor problems. Every SB applies to my engine. These were design equipment problems and properly maintained, the engine still delivers excellent performance. What has it cost me: A stator, fuel pump, both carbs, and starter replacement, rebuild of my turbo, and repair of the turbo bracket, new hoses, and required education on carb and TCU maintenance and service training. What have I gotten in return, 140-150 knot plus cruise performance at 10,000 feet plus 700-800 fpm climb all the way to 10,000 ft. I never fear a hot day high density altitude takeoff and I spit on carb icing and shock cooling.
The early 912S have had the following: Rough starting, requiring new or modified ignitions, exhaust failures due to harmonic vibrations and that ugly shaking on start and stop, cracked engine blocks, carb heating concerns, stator problems, starter cranking problems, and carb problems also. They do not perform well above 7500 feet due to poor leaning and significant power loss due to altitude is evident.
The brand new engines of both 914 and 912S are much better engines. Much has been learned and incorporated in the last 20 years. The 912iS is not very maintainable in the field due to its proprietary electronics, but it performs superb in comparison to the 912S in economy at cruise. No difference on takeoff performance at sea level to speak of, but better performance at higher takeoff density altitudes...
Bottom line:
If you want good takeoff, climb and cruising performance, get a constant speed with either engine. Research maintenance problems and servicing for the prop of choice. If you are concerned about high altitude operations, get a 914. If you just intend to fly at lower altitude and short hops, a 912S is an excellent value. Even equipped with a fixed pitch prop, it is a nice $100 hamburger cruiser to join your Light Sport buddies at a nearby airport. I prefer high and fast in my area of operations where I need to get to 10,000 feet to clear clouds, and find some cool air and a comfortable range of 300nm. Cruise efficiency is at my choice, from 25-35anmpg (air nautical miles per US gallons) depending on power setting.
Full disclosure, I am a dealer for Airmaster and somewhat predujudiced after 10 years of replacing other brands here in the US.
See my website (www.customflightcreations.com) and click on the techniques section on many topics from cooling to maintenance as well as performance testing and an article on choosing the right propeller options for your aircraft. This section works for other brands of props as well (not the Ivo as friends don't let friends fly with an Ivo) MT, Airmaster, Woodcomp are all very close in performance but differ in weight, maintenance and operational problems such as time to mandatory overhaul and servicing requirements, corrosion and rot problems, blade wear due to weather and foreign object damage, component life limits, finish problems (peeling paint and cracks), controller operations, failure rates, factory/dealer assistance and availability, finding an English speaking service rep, etc..
An airplane is 20,000 compromises flying in close formation, the choices are yours. Choose wisely.
Best Regards,
Bud Yerly
Custom Flight Creations, Inc.
US Europa and Airmaster Dealer
www.customflightcreations.com
Sent from Mail for Windows 10
From: William Bliss (william(at)wbliss.co.uk)Sent: Sunday, September 18, 2016 3:58 AMTo: europa-list(at)matronics.com (europa-list(at)matronics.com)Subject: 912ULS to 914?
--> Europa-List message posted by: William Bliss <william(at)wbliss.co.uk> Dear All I am struggling to get out of a 450m grass strip 2 persons and full fuel (no baggage). Has anyone got experience of the improvement in take off performance with the Rotax 914 over the 912ULS? I expect this has been debated before but I cannot find a way to search the matronics website for it. Thanks William Bliss G-WUFF Mono Classic XS firewall forwards. 912ULS, Woodcomp SR3000, Smartcontroller =========== st Email Forum - pa-List">http://www.matronics.com/Navigator?Europa-List =========== p; - MATRONICS WEB FORUMS - ums.matronics.com =========== p; - NEW MATRONICS LIST WIKI - matronics.com =========== p; - List Contribution Web Site - p; -Matt Dralle, List Admin. http://www.matronics.com/contribution ===========
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Roland
Joined: 30 Nov 2009
Posts: 334
Location: EDLE
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| Posted: Mon Sep 26, 2016 1:02 am Post subject: Re: 912ULS to 914? |
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Bud, thanks (again) for sharing your knowledge. Couldn't agree more to all you've said about the 914 and CS-prop.
Roland
PH-ZTI
XS TG 914
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