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AS350 Astar/Squirrel

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AS350 Astar/Squirrel

Old 5th Apr 2018, 15:19
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If only they could get the translation right. I'm assuming that jackstall makes the controls rigid? But yes, hardover describes it better, though still similar to me. It makes the point that it doen't do to skimp on the hydraulic training for this beast....
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Old 5th Apr 2018, 16:32
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No, the jacks collapse as the aerodynamic backloads from the rotor overpower the hydraulics.

Since the highest aero loads are on the retreating side, aft of the lateral position, it displays the same symptoms as retreating blade stall - ie a roll to the right and a pitch nose up.

Just like RBS, it is encountered at high AUM/high speed/harsh manoeuvring/ham-fisted piloting combinations.

On the Gazelle, it was demonstrated in a dive to VNE at MPS (168 kts with about 14.5 degrees of pitch) and still required a hard pull to get it in.

The other demo was in a hard left turn with a hard pull - never done in a right turn as you could end up inverted.
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Old 5th Apr 2018, 19:43
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Ah - a servo runaway as opposed to aerodynamic forces overcoming the hydraulic input. Got it. Chalk and cheese, methinks.
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Old 6th Apr 2018, 04:28
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Yes, apologies for the mix up.
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Old 6th Apr 2018, 07:58
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Paco, if someone of your extensive experience and knowledge had misunderstood it, it is no surprise that the knowledge of newer pilots in the industry is sketchy on the subject
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Old 6th Apr 2018, 14:37
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Yes, that's the disturbing thing! Constantly trying to battle myth and legend!
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Old 6th Apr 2018, 15:23
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Originally Posted by paco
If only they could get the translation right. I'm assuming that jackstall makes the controls rigid? But yes, hardover describes it better, though still similar to me. It makes the point that it doen't do to skimp on the hydraulic training for this beast....
Jackstall does not make the controls 'rigid' you can still move them. (350D) It was discussed in the RFM. We used to demonstrate in training. It felt a little like a hyd. failure on a 206 until you recovered from the condition.
Perhaps someone with access to an AS350D RFM will be kind enough as to post the actual reference.
As an aside we had a new Astar pilot trucking along at max cruise who pushed the hyd. cut off on the 350D collective..He said it got really interesting as the beast pitched up and banked right in a most startling manner.
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Old 6th Apr 2018, 15:41
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Originally Posted by [email protected]

The other demo was in a hard left turn with a hard pull - never done in a right turn as you could end up inverted.
On my QHI course, my instructor did just that and we did a complete roll back to wings level. Instructor change the next day!
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Old 6th Apr 2018, 17:16
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Fortunately you didn't do that to me on mine!!!
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Old 7th Apr 2018, 09:41
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Once was enough!
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Old 7th Apr 2018, 10:08
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From AS350B3e RFM

Maybe that's what you're referring to Albatross..
Attached Images
File Type: png
Servo Transparency.png (278.0 KB, 73 views)
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Old 7th Apr 2018, 12:06
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Where it says 'reduce the severity of the manoeuvre' it really ought to specify that if you have pulled up or rolled and pulled into a turn, you need to reduce the aft cyclic as the increase in G is what has overloaded the jacks.
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Old 7th Apr 2018, 17:02
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Originally Posted by MitchStick
From AS350B3e RFM

Maybe that's what you're referring to Albatross..
Not what I remember from the 350D but close enough.
Many moons since I flew and did training in the D.
Can't find my manual...it is buried deep in a box in the basement.
The 355 had a "limit light" (due to the dual HYD system ) to advise you had reached the G limit of the aircraft.
Thanks.
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Old 7th Apr 2018, 18:05
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The 355 had a "limit light" (due to the dual HYD system ) to advise you had reached the G limit of the aircraft.
They took that idea onto the 365 as well and it illuminated as the aerodynamic backloads compressed the stbd lateral jack (retreating side again) and made a microswitch there.
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Old 9th May 2018, 16:19
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Anybody flying the AS350B3+ finding that the N1 limit changes with altitude? Manual gives it as 101.1% N1 take-off limit(5 minute limit) at Hp = 0 ISA.
I am hitting the N1 limit at 100.4% to 100.6% at around 7000-8000' PA & 20 degC.

Any info from the guys with high time on B3+ would be greatly appreciated,
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Old 25th May 2018, 01:34
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Originally Posted by [email protected]
They took that idea onto the 365 as well and it illuminated as the aerodynamic backloads compressed the stbd lateral jack (retreating side again) and made a microswitch there.
Yes, 330 daN if I remember correctly. It also illuminates and "gong" for Ng and Q limits.
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Old 26th Nov 2019, 19:09
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AS350b3 Power Check

I no longer have the manuals, so can anyone tell me please, AS350B3 Power check when you have "BAD" numbers, what are the parameters? (+/- %)
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Old 27th Nov 2019, 13:31
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Originally Posted by GOMflyboy76
I no longer have the manuals, so can anyone tell me please, AS350B3 Power check when you have "BAD" numbers, what are the parameters? (+/- %)
Insufficient information. 2B, 2B1 or 2D?
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Old 28th Nov 2019, 11:07
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AS350B3 has a 2B, otherwise he would have said B3+ or B3e I assume
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Old 28th Nov 2019, 13:30
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Originally Posted by MitchStick
AS350B3 has a 2B, otherwise he would have said B3+ or B3e I assume
To my knowledge, I don’t believe the ‘+’ was ever adopted as the official nomenclator, at least never in the US. The RFMs simply refer to the variants as “AS 350 B3 Arriel 2B” and “AS 350 B3 Arriel 2B1”. The current model designation is “H125”, however the RFM is still entitled “AS 350 B3e”. IMHO, in the US, the manufacturer has always clouded the differences to the point of it ostensibly being a contributing factor in several accidents.
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