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AW169

Old 9th Feb 2016, 22:19
  #21 (permalink)  
 
Join Date: Aug 2003
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APU mode is normal on all 169
Ok, you are referring to the ability to run an engine without turning the rotor. Sorry, I was thinking actual APU like the 189.
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Old 10th Feb 2016, 03:26
  #22 (permalink)  
 
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Yes, the AW169 has an "APU" mode which matches the Accessory Drive so familiar to a Sea King driver: but all sorted via touch screen and simple switchology! It would be a big safety and convenience feature for keeping systems such as the air-con running with blades stopped, the No 1 drives everything at idle with low fuel burn whilst No 2 is shut down and blades stopped.

The touch screens are immensely intuitive, and won't give an option (icon greys out) unless it is available. Current software issue is 90 seconds to get the screens online with systems showing for start, Finnmechanica is working on a reduction as well as sorting the nearest GPS facility and the collective hunting. It is smoother hand flown (in some circumstances) than allowing the collective to hunt around, although it does settle down given enough time. The weather radar goes to standby with WOW, but can be inadvertently switched on when on the ramp. Not so much of an issue for us old timers but a trap for young players used to the software protecting them.

Good seats with plenty of adjustment (bliss) and great vision from the front. Comprehensive display with stunning screens. No run-down time whatsoever for the engines, just turn them off. Very difficult for any turbine experienced pilot to get used to! No boost pump at all, so with one engine shut down the fuel for that side is unable to be used by the good engine: no low level fuel interconnect. Debatable recognition of engine reliability?

Externally: huge coanda strakes built into the tail boom. Tail rotor control via a cable. Tail rotor hub is akin to a main rotor head, and a three bladed T/R on a five blade M/R just looks weird. Passenger retracting steps are huge, and the underbelly storage is almost big enough to be taken for a firefighting belly tank! Cargo bay access is on the left side again, still out of sight of the pilot in SP ops.

Rear cabin: nice seating, as you'd expect. LED lights default on when the aircraft starts, and require the (hot) lamp cover to be pushed in order to turn off; each of them, and there are 4 on each side! Mood lighting controllable from a touch screen alongside the left rear passenger seat, who is also the only one with intercom to the pilot.
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Old 10th Feb 2016, 04:04
  #23 (permalink)  
 
Join Date: Aug 1999
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AW169 cockpit



This shows the engines prior to start, with No 1 connected rather than APU. The fuel tanks have no low level interconnect, nor boost pump to feed the 'other' engine.



Overhead simplicity!



Touch screens = sticky fingermarks!







Decent seating



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Old 10th Feb 2016, 06:14
  #24 (permalink)  
 
Join Date: Aug 1999
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AW169 external

This is first of type on the CASA register, and also as a Part 61 registration for the pilot took proof that the Italian factory pilot who gave him his type rating was approved to do so. Bl**dy CASA gets worse and worse





All that tail rotor, controlled by a cable!



One heck of a coanda strake



Reasonable boot space



Massive retracting steps and underbelly fitting; or is it really a firefighting belly tank



Electrically operated gear, currently 80kias limit but looking to increase up ~120kias

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Old 10th Feb 2016, 06:44
  #25 (permalink)  
 
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AW169 cabin

These are only iPhone 6 photos, so a bit grainy in places: sorry!

Three reclining captains chairs facing for'rd, four fixed facing aft



Dinky little touch screen by the left rear seat. Weird to see the DOS instructions as it boots up!



Mood lighting controls. Hmmm



and the lighting strips. The LED emergency lights to the left of the strip default 'on', and the light cover has to be pushed to turn it off. And they are hot! But the aircon is the bee's knees, plus it runs off the APU mode.

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Old 10th Feb 2016, 13:10
  #26 (permalink)  
 
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Great pictures John. Thanks.
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Old 10th Feb 2016, 15:50
  #27 (permalink)  
 
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Great cockpit. I like the visibility and the big screen instrumentation.

Is that a Ram mount for an iPad, Mini or Air? Coanda strakes are effective enough it only needs 3 blades on the tailrotor? I see you're strobing the MR, is it as smooth as a 430 or as rough as a 139?
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Old 10th Feb 2016, 16:29
  #28 (permalink)  
 
Join Date: Sep 2004
Location: daworld
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malabo, if you have a rough 1/rev in a 139, you need to track and balance.
I've never looked after a 139 that was higher than 0.08 ips lateral or vertical.

If you're talking a rough 5/rev, play with the tuning weights under the floor. Don't go by the book, get it close using book values and then play with it each flight to optimise it for your cabin and aircraft configuration.
Or, just go buy the MVA. You won't be disappointed!

The 139 should only be rough when getting close to Vne or during translational. In cruise it should be nice and smooth.

Nice photos of the cockpit John, but I do note on the Fuel page that there is a corss feed interconnect in the tank. It is not at the bottom, but looks like it is placed about the same as it is in the 139, so if you lose an engine in the 169 you will have some fuel that you can't get out, but most will transfer across.

An old brochure I just dug up confirmed the interconnect. It says 200 liters will fill into the left tank before it reaches the interconnect. So if you have an engine out, there will be a maximum of 200 liters that you can't use. About the same as the 139 if you have a boost pump fail.

Now how to get the training course and not have to pay for it.......
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Old 10th Feb 2016, 17:33
  #29 (permalink)  
 
Join Date: Feb 2006
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Kent Surrey Sussex Air Ambulance

Kent Surrey Sussex Air Ambulance received their first AW169 (photo courtesy of Finmeccanica)

cheers

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Old 10th Feb 2016, 20:06
  #30 (permalink)  
 
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So if you have an engine out, there will be a maximum of 200 liters that you can't use. About the same as the 139 if you have a boost pump fail.
Not sure what you mean by 200 liters you can't use. There is no situation that you can't use all the fuel in the 139.

The level where it becomes 2 separate fuel tanks in the 139 is 228 Kgs. If you lose a boost pump in AEO mode the engine driven pump can draw all the fuel in the respective side of the system by closing the cross feed. In OEI by opening the cross feed even in a dual boost pump failure (total electrical failure) the operating engine driven fuel pump can draw the fuel from both sides until the total fuel is exhausted.

Last edited by Outwest; 10th Feb 2016 at 20:18.
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Old 10th Feb 2016, 22:18
  #31 (permalink)  
 
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[Not sure what you mean by 200 liters you can't use. ]

There are no boost pumps in the 169. If you lose an engine, there is nothing to pump/suck the fuel out of the failed side tank once it reaches the connecting flange.
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Old 10th Feb 2016, 22:59
  #32 (permalink)  
 
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I was referring to his statement that it is the same as the 139.

I have no knowledge on how the 169 is set up although I do know that you are correct that they do not have boost pumps. I would find it very odd that AW would have a design that would allow you to run out of fuel in an OEI situation and still have 200 liters onboard.
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Old 11th Feb 2016, 02:22
  #33 (permalink)  
 
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Outwest is correct, I had a brain fart there. You would need a boost pump fail AND a Xfeed fail to lose the 228kg.

I would assume the 169 has a Xfeed valve too???
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Old 11th Feb 2016, 03:31
  #34 (permalink)  
 
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If there are no boost pumps, there is no need for a crossfeed.
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Old 11th Feb 2016, 04:44
  #35 (permalink)  
 
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If there are no boost pumps, there is no need for a crossfeed.
No, as long as there is an inter-connect between the fuel systems. I think everyone is just wondering how you access the fuel from the opposite side in the event of OEI.
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Old 11th Feb 2016, 07:58
  #36 (permalink)  
 
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"there is nothing to pump/suck the fuel out of the failed side tank once it reaches the connecting flange."


"I think everyone is just wondering how you access the fuel from the opposite side in the event of OEI."


On the 139, crossfeed is only controlling which engine the fuel is directed to, not which tank. Below the interconnect fuel is distributed equally by gravity. When fuel reaches a level below the interconnect, the crossfeed valve has to be open to deliver fuel to the opposite engine. It is fed up through the lines, not via the interconnect flange. It needs the boost pump on the shut down/failed side to match the input pressure on the good engine side (which won’t have had its pump switched off as part of a shut down procedure). If the pump is failed on the shut down side, switching the other one off should solve the pressure imbalance.
If it’s a similar design on the 169, without boost pumps there should be no significant pressure disparity, so just make sure that crossfeed is open (as you said Outwest).



TT

Last edited by Torquetalk; 11th Feb 2016 at 08:14.
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Old 11th Feb 2016, 08:37
  #37 (permalink)  
 
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If itís a similar design on the 169, without boost pumps there should be no significant pressure disparity, so just make sure that crossfeed is open (as you said Outwest).
That's the problem, it has been mentioned in this thread that the 169 does not have a crossfeed valve. So, if that is the case then the only other option would be an interconnect valve ( like a 212) to allow fuel to flow between the 2 sides.
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Old 11th Feb 2016, 08:40
  #38 (permalink)  
 
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Interesting question about the OEI scenario

I'm not a 169 man but I do recall my colleagues saying that there are no booster pumps in the 169 and with the same basic tank design as the 139 there will be unusable fuel in the tank supplying the dead engine.

The laws of physics dictate that if the engine sucks through the crossfeed then in theory both tanks will supply the one live engine. I suspect that those same laws of physics will generate a pressure drop across the crossfeed lines leading to a preferential supply from the most direct tank - the one supplying the live engine.

As the fuel level drops the imbalance will grow until the live engine's supply runs out. This will turn into a big headache because once the engine sucks air it will wrap its hand in. Methinks that hauling that inaccessible fuel (200 litres?) around will become tiresome for it can never be part of your reserves.

The stopwatch is running on how long it will take for the booster pumps or transfer pumps or low-level transfer valve to appear.

Now I will go into work and get beaten up by my 169 buddies.

Aye G.
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Old 11th Feb 2016, 10:18
  #39 (permalink)  
 
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Nice looking screens.
How many of the contributors on this thread are 169 pilots or have been on training course, because to me it would appear there is confusion as to the way the system operates Same as Glasgow
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Old 11th Feb 2016, 10:55
  #40 (permalink)  
 
Join Date: Apr 2008
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A good vid of the AW139 fuel system for comparison.



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