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Introduction
#11
In the R-22, we turn the throttle to idle,while dumping the collective. The engine rpm goes to idle, but the rotor stays at 100% due to the sprague clutch function. In the R-22, the governor only functions above 80%. I don't know about the XET. And the 285 does not have a governor.
XE285 #1329 N869DJ
Start: June 2018
Done:  Sep 12, 2018  Sleepy 
AWC Issued: Sep 26, 2018  Big Grin  
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#12
Will,
   Part of what the governor does is adjust fuel flow to stabilize rotor RPM within the governed range, no matter what the flight conditions.  We used the twist grip in a few emergency procedures like stuck pedals and overspeeding, but that was the only time.  I never had an actual situation when I had to manually manage the rotor RPM.  You could underspeed a head if you REALLY tried, but it became evident quickly when you started losing turns.  Then you just had to stop whatever maneuver you were in.  We really worried about overspeeding the head.  The H2 had flaps on the rotor blades so we could trim out vibration in flight.  The downside to that was that we had small control rods going up the mast and out to the flaps.  Overspeeding could really damage them.
    When you dumped the collective for an auto, the RPM would build maybe 1 to 1.5%.  That was about it.  2% overspeed was the operational threshold.  At 4% you had to inspect (and most of the time, replace) the head and control rods.

As far as the Mosquito goes, I don't know. I would assume all governors work about the same...But you know what assuming does...

Dick, you are correct. The governor only functions when the engine is set to a percentage of 100% I don't remember what the H2 was. But as soon as you twisted the throttle to idle, governor was disengaged.
Fly Navy,

Scott Langley
MCSE CEH CISSP

XET #1337 N334HY
Start: Sept 2018 ??
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#13
Hi and welcome to the Mosquito Community !

The XE285 can have an optional governor which works exactly as the R22 does but it is better to learn without it. About the XET it is on or off, no idle possibility... As a futur XET pilote in order to keep your auto's skills at good level it is recommended to regulary practice it on a R22 or a Schweizer 300 which is very similar to the Mosquito feeling...

For more infos on how the XET does in auto, this link page give some good take on it (scroll to RSM guy post message).
http://forum.mosquito-helicopter.info/sh...hlight=xet
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#14
Hello Scott!! Very late welcome from a fellow HSL Naval aviator, also XET owner, N315FC. I live in Abilene, TX. Line pilot for Air Evac Lifeteam and Navy reservist with 7th Fleet.

Youtube and iG: rotorlyfe
Not much there yet, thinking of selling my baby, just don't need her to build hours anymore. I'm also jealous of your awesome serial number!
Owner N315FC   XET built by Scott Seaner
CFI/CFII, LCDR USNR
Line pilot at Air Evac Lifeteam, AE63 Abilene, TX

YouTube/iG : RotorLyfe
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#15
Hello Rotorlyfe,

Just read you are going to sell your XET... Could you send me a pm to fele@skynet.be to know your asking price and the nbr of hours you got with your baby... if it still for sale of course.

Thank's
Fred
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#16
Sent you an email, but it got kicked back. Check your PM folder.
Owner N315FC   XET built by Scott Seaner
CFI/CFII, LCDR USNR
Line pilot at Air Evac Lifeteam, AE63 Abilene, TX

YouTube/iG : RotorLyfe
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#17
Welcome to the Mosquito Nation Scott! To answer your question about doing autos with an XET. First, what do you mean by you want to do autos? Do you mean terminate to a hover or to the ground? If you mean terminate to a hover then rolling the throttle to idle (or any other position than fly) shouldn't be necessary. You can just reduce the collective and as soon as the rotor goes above whatever the reference rpm is (I assume 100% NR) the turbine should reduce fuel to maintain the engine rpm (100% NP). Just like the turbine helicopters you flew in the Navy if the NR is higher than the NP then the rotor is decoupled from the engine and in autorotation. The Mosquito rotor head has quite a bit more leeway than the narrow overspeed limitations you cited above (I assume those were for the Kaman Sea Sprite). When I did autos in the Mosquito XEL I had to roll to idle or the engine would overspeed. As I understand, the turbine used in the XET has a very simple inertial governor (instead of an electronic governor like the one on the turbines used in other helis like the Helicycle). This inertial governor is either engaged or disengaged based on the rpm set by the throttle input into the fuel control. It is like the prop governor used on most turboprop planes. If you are planning on doing autos to the ground then obviously you must go to idle and although I have flown several of the turbine Mosquitos I have no experience with doing autos in them and I will defer to someone who has. Good luck on your Mosquito adventure.
Mark Thompson
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#18
Hi Scott, I tried a couple hovering simulated engine failures in my XET today. First one was from 2 feet, second was from about 5 feet, initiated by rolling throttle off smoothly about a quarter of a turn while freezing collective, allowing the Nr to droop a few percent just to get the audible change in rotor pitch and put in a correct amount of right pedal. This was over thick grass on forgiving topsoil, since we had a lot of rain here 2 days ago. Once I gently touched down, kept pulling collective just to see if it would want to come back up, which it really wanted to. That tells me there really is a "safety margin". I wasn't looking at the EFIS, just listening to the rotor, and looking outside.

I am comfortable with hovering autos (and other flavors) from higher altitudes in a Bell 206L4 which is my daily work helicopter, which with SAS off behaves very similarly to an XET power off in many respects. I can't speak for Robbies. I'm an H-60 NATOPS guy myself, and pulling the PCLs back in a low hover doesn't quite compare to the XET. The squirreliness just isn't there in an H-60.

All that being said, I don't think I'll be doing much more of that since I don't want to ding my perfect aircraft while it's for sale. I feel confident the muscle memory from the forgiving 206L4 has me in the right mindset to deal with a sudden hovering engine failure. It's all about listening to the rotor head, the left arm takes care of the rest.
Owner N315FC   XET built by Scott Seaner
CFI/CFII, LCDR USNR
Line pilot at Air Evac Lifeteam, AE63 Abilene, TX

YouTube/iG : RotorLyfe
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#19
Rotorlyfe,
Great to see another LAMPS guy. I finished my career as an FTS, so know and line the Reserve world. Sounds like you're having all kinds of fun flying. I never could get anyone to trade flight time for work, which is why I ended up here.
I spent some time talking to Dwight on Monday and he added some info on this engine and autos. Glad to hear your hovering full autos went well. I'll just have to wait and see when I get done.

Sent from my SM-G955U using Tapatalk
Fly Navy,

Scott Langley
MCSE CEH CISSP

XET #1337 N334HY
Start: Sept 2018 ??
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