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Dash 8 power & condition levers use

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Dash 8 power & condition levers use

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Old 21st Jun 2006, 21:02
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Dash 8 power & condition levers use

Hi,

Can any of you please explain me how are they used and what do you control with them depending on the mode you are?

Thank you.
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Old 21st Jun 2006, 21:25
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Condition levers have two jobs.

First is as a fuel shut off.

Second they control propeller RPM.

There are 5 positions for the CL's.
- Fuel off
- Start/feather
- 850rpm
- 900rpm
- 1020rpm

To start an engine you simply move the CL to start/fx once you have positive engine rotation. This introduces the fuel and allows FADEC to control the start (if it's working). Once the engine and prop have stabilised the CL is moved to max/1020. The FADEC controls prop rpm up to 660rpm (ground range). You now use the Power levers to change...err...power. All the while the prop is at 660rpm.

To get take off power. There is a Power Lever Angle (PLA), which is basically a microswitch, that signals the FADEC to increase prop rpm to 1020. The Power levers are then put into the Rating Detent. The rating detent signals FADEC to provide the selcted power ie. T/O power.

Once airborne the condition levers are moved to either 900 or 850 rpm. 900 with max climb power (torque) was designed as climb power and 850 max cruise power for cruise. However, in our company we use 850 rpm with max climb power/torque for the climb. This is achieved by selecting the CL to 850 and selecting what they call a "soft button" on the Engine control panel to select Max climb power (torque).

Generally the Power levers are left in the detent but on good days the aircraft may over speed so you can then move the power levers out of the detent and control power/torque yourself.

Hope that's of some use.

CM
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Old 21st Jun 2006, 21:43
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I'm guessing that the above post is on the Q400.

I fly the Q300 which doesn't have FADEC. Slightly different on the Q300 in that we use either 900rpm for the climb or 1050rpm if we want to climb a little bit quicker.

We don't use any of the climb modes switches.

Nice to read the differences.
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Old 21st Jun 2006, 21:48
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Oooops! Sorry for the glaring ommision!

It is for the 400. I never got my hands on the 300. Do you still have the detents or is it all manually set and adjusted?

CM
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Old 21st Jun 2006, 22:26
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and...

Where I operate we use the CLs @ 1200 for TKOF power, 1050 or 900 for climb and 900 for CRZ. All for the 100&300. All landings are at 1200.

There is a switch for different ECU modes on the 300 (and maybe on the 200?), but I guess DH never sorted out how to make it work. Iīve been told by our tech dept. that there arnīt any wires behind that switch!!! (kind of like a panic button which you can buy at Sportys!)
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Old 22nd Jun 2006, 07:41
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The switch with no wires

Hi

the switch with no wires was used on the 200(Iīm not not sure if also in the 100).

He is called "ENGINE ECU RATING SELECTOR and has three selectable positions:

TOP - T7O torque
MCL - Max. Climb PWR
MCR - Max. Cruise PWR

If seleceted aon both Torque Indicatorīs will appear a tourque bug wich shows you the right torque setting. So you dont have to check a power table.

The reason why itīs not wired in the 300 - I donīt know. Iīve just herad a long time ago, that DH said that it was cheaper to let it install than to create an own cockpit for the 300.

My little news

Greets
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Old 22nd Jun 2006, 23:04
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The switch with no wires actually HAS wires

This "rotary selector" (4 pos) is used by the engineers to rig the ECU's. With two additional 'secret' buttons under the pilots' sidepanel (behind the velcroed-on panel, just aft of smoke goggle) and rotary knob selections they can adjust the engine to produce a specific torque for a PLA. Talking -300 series, btw.
Other proof this switch is wired may be produced by selecting any non-TOP position before Take-off: this will trigger the Take-Off Warning.
Just my $0.02 of course....
PD
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Old 22nd Jun 2006, 23:12
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hi, anybody know of dash 8 jobs in middle east?
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Old 23rd Jun 2006, 13:14
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For the DHC8-200,

To clarify dash8jockey's answer, when the ECU selector is placed in the TOP position, the torque bugs are removed from view and the correct power setting for take-off is set without reference to them.

After take-off, the ECU is selected to MCL and climb power is set by reducing the torques (with the power levers) to about 85% then bringing the condition levers back to MIN (for a 900RPM climb setting.) The torques increase to about 110% as the RPMs are reduced and then you can fine tune them for max climb power (114% at sea level) and turn the synchro-phase on.

The condition levers then remain at MIN until being returned to MAX (1200RPM) while configuring for landing.

All further power adjustments for climb, cruise, and descent are made using just the power levers. The ECU is selected to MCR for the cruise as appropriate.

Although the ECU provides bugs on the torque guage as a guide to the correct power setting, it is only supposed to be used as a guide, and crews are required to cross check the bug figures with torque settings from the operating data manual. All Dash 8 crews do this religously .
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Old 23rd Jun 2006, 14:19
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Originally Posted by SlowAndSilly
and...
All landings are at 1200.
Its interesting to see other companies procedures. Our company (100,200,300) lets us land with props 1050, and encourages it, unless certain conditions are present (low wx, flaps 35, windshear possibility, good chance of a go around, and assorted others). Its quieter too. Ive never done it myself, but some guys talk about landing with props 900. Like i said, only heard about this . In our 100's we switch the ECU after t/o, no torque bugs. In our 200's we switch the ECU and torque bugs pop down. In the 300's we just leave the ECU in TOP. At least for the 100, if you keep the NH at around 95% it will give you within 2% of what the charted climb torque would be off the charts. Works really well. You dont even need the charts anymore with that rule of thumb.
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Old 23rd Jun 2006, 21:36
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Originally Posted by DHC8-FO
Its interesting to see other companies procedures. Our company (100,200,300) lets us land with props 1050, and encourages it, unless certain conditions are present (low wx, flaps 35, windshear possibility, good chance of a go around, and assorted others). Its quieter too. Ive never done it myself, but some guys talk about landing with props 900. Like i said, only heard about this . In our 100's we switch the ECU after t/o, no torque bugs. In our 200's we switch the ECU and torque bugs pop down. In the 300's we just leave the ECU in TOP. At least for the 100, if you keep the NH at around 95% it will give you within 2% of what the charted climb torque would be off the charts. Works really well. You dont even need the charts anymore with that rule of thumb.
We used to do landings with 1050, but unfortunately we had some incidents with overtorque during MAPs. There landings are now strictly 1200. In the books are graphs and supplements for 900 landings aswell. I believe Tyrollean do them?
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Old 23rd Jun 2006, 21:59
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..

They might, im not sure. I wish theyd let us do 900 rpm landings. Stealth mode.
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Old 23rd Jun 2006, 22:41
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We can now do 850 landings on the 400.

There's a soft button "RDC NP" which is pressed and ten the CL's are moved to max but prop rpm is kept at 850. If a GA is done the FADEC automatically increases to 1020 and max power. No chance of over torque.

I love FADEC
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Old 23rd Jun 2006, 23:13
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...

Wow, 850. Im jealous, I bet its really dang quiet. Can you use that with any flap setting? What are the flap settings on the 400? Same as the 1/2/3's? I wish the boneheads at our company had gotten 400's when they were giving them away. Ill probably never get to fly it now. Oh well, im just glad we have APU's across out fleet. I know some dash's dont have APU's.
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Old 23rd Jun 2006, 23:24
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It's dead quite!

You can use all flap settings as long as the performance says so. There is a slight detriment to max landing weights but only really affects you if it's wet.

Flaps are 5, 10, 15 and 35. 15 and 35 are standard landing settings here. 5, 10 and 15 for take off. Same as the 300? I never flew it.

Our APU's keep breaking. I think more than half the fleet has got a buggered APU. Perfect for the summer!
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Old 24th Jun 2006, 01:50
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Don't know about the 300, but flaps 10 is not selectable in the 200. We have 5 and 15 for takeoff and 15 and 35 for landing.
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Old 24th Jun 2006, 08:46
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hi
yep, can confirm that 900 rpm is the preferred setting for landing on the 300 at tyrolean. restricted to non-contaminated runways, tailwind less than 10 knots and a couple of other sensible considerations. i land with 900 rpm about 90% of the time. i donīt think that the danger of overtorquing is significant as the go-around procedure calls for the condition levers to go to max first and then for the power to be set. positioning the condition levers at max will initially create a torque drop.
850 rpm is preferred on the 400 for landing, even with flaps 35. but, hell, the damn thing shakes with flpas 35 set. quite scary when doing it for the first time!!
cheers
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Old 25th Jun 2006, 14:36
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Cool

Flap 15 at 850 rpm RDC Np (Q400)
bliss....
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