King Air Propeller Demonstration
Ғылым және технология
With the cowls off, this video demonstrates how the prop levers and linkages work to command the governors to increase, decrease, or maintain propeller RPM as required by the pilot.
Edit: I’ve added the following text to answer some common questions in the comments.
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What prop settings do you set during different stages of flight.
In essence, regarding prop lever settings, the only pilot action during a “normal” flight in this type of aircraft is as follows:
-Props full forward (fine pitch) for taxi and Take Off. See Note 1 below.
-Adjust the props to “Maximum Continuous RPM, or Climb RPM shortly after take off. See Note 2 below.
-Reduce Prop RPM for the cruise. See Note 3 Below
-During the approach phase adjust your props to
full forward for the landing (reverse thrust) or for the anticipated “go around”. See Note 4 Below.
That’s it. The rest of the time, the governor works to achieve the RPM that the pilot has “asked for”/selected. So when there is excess power, it simply reduces the pitch of the blades to take a bigger “bite” of the air.
Notes.
Note 1: The props won’t achieve the High RPM you require, until you apply sufficient power using the power (thrust) levers to turn them fast enough. Once you have enough (and excessive) power, the governor will continuously adjust the propeller pitch to maintain the RPM you requested.
Note 2: In the C90GTX, the difference between Maximum RPM (time limited) and Maximum Continuous RPM is very small. Just a fine tickle back of the prop levers. If the props are rigged correctly, this is a change of 1,926 RPM to 1,900 RPM. In other King Air models, the difference between Max RPM and Max Continuous is more of an adjustment. (300-400 RPM in the in the models I’ve flown)
Note 3: Refer to the Cruise Tables in your Pilot Operating Handbook. In this particular model, you can leave the props at 1,900. We do however tend to adjust them to 1,800 for longer cruises, because it changes the “tone” of the props to a more comfortable one for passenger comfort.
Note 4: Pilot technique differs here, based on the types of props you have fitted, runway available and passenger comfort. In the C90GTX, I always adjust the Props to full forward in the final approach phases of a flight. That way, the “Reverse Thrust” is ready on the ground and I simply have to put the power levers in reverse. Same with a go-around... it leaves me less things to do.
In the B200 or other models of the 90 that I’ve flown, you could be adjusting the props from 1,600 to 2,200 RPM ready for the reverse or go around. This can have quite a noise increase for passengers. So, many pilot choose to leave the props where they are until after touchdown, when they will then whack prop levers full forward before applying reverse thrust. This of course, is runway length and other conditions permitting.
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Another common question is “why do you manually close the gen ties before start”.
Lazy but most obvious answer: Because the C90GTX POH says so!
Real explanation: the C90 GTX has a “triple fed” electric bus system. The flashing beacon light outside the aircraft, operates off the Left Bus.
So until the left generator bus is online... the Beacon light won’t be on and flashing outside, regardless of the Beacon Light switch position. So you manually close the gen ties before start for that reason.
Пікірлер: 260
Either thats a brand new aircraft, or someone has been taking very very good care of the control panels. Not a scratch on them, they all look brand spanking new
@Mode_Sierra
3 жыл бұрын
Thank you! Aircraft about 7 years old and just over 1,000 hours!
@slashz0r
3 жыл бұрын
@@Mode_Sierra it's very obvious you give this craft the attention/care it deserves
@Mode_Sierra
3 жыл бұрын
@@slashz0r Credit goes to the engineer/mechanic. I look after it in the sky.
The King Air is just a gorgeous turboprop inside and out. But, really love the cockpit.
@davecrupel2817
3 жыл бұрын
It's also a ferocious sounding plane. That prop tone you hear at 2:10 is often the loudest sound at the airport if it isn't a military base. I call King Airs the Dodge Hellcats of General Aviation. Because they sound mean as can be, they sound powerful, and they are a joy to listen to. (Even a bit humbling when you're right up next to one while its running) Even if you need hearing protection within 700 feet of them 😅
@HekateMGO
3 жыл бұрын
As someone that’s worked on these things & hates them with a burning passion I just wanna say that I appreciate people like you who love them. They do look good though. 😂
@goofygolfer56
3 жыл бұрын
Yeah, it’s gorgeous, but the inboard tanks between the engines and fuselage are a pain in the a$$ to get to and fuel!!!
@Posttrip
3 жыл бұрын
@@goofygolfer56. Not ‘signal point?’
@goofygolfer56
3 жыл бұрын
@@Posttrip Nope. One, two or three tanks per wing with the mains being between the engines and fuselage
Brilliant video, simple to understand, amazing to see the feathering mechanics at work and whilst for many this might seem banal, I found it fascinating.. Well done lad for a super piece of footage and delivery.
@sigistrele5835
2 жыл бұрын
I agree! And I love Beaker!! Greetings from Austria
@Mode_Sierra
2 жыл бұрын
You’re very welcome!
Very interesting, thanks!
Good illustration of how many systems and controls come into play just to start the engines. Thank you!
I don't fly so this means nothing to me but it came up in my feed so YT felt I needed to see this. Was not disappointed. My inner geek has been satisfied.
@Mode_Sierra
3 жыл бұрын
Hahaha. Glad I could help and find mutual geekinessz
Thanks, believe it or not I've always wondered what the change in engine noise was on start-up. Now I know it's the revs changing as the governor takes over.
I was watching and just thinking about how much I love the sound of turbines when you said it for me!
Reading about this in theory makes me scratch my head wondering what the heck are they talking about. Thanks to your video I can finally visualize it properly.
This guy is a legend. He says Governor like a proper champ, and he sets the prop rpms to 420 in the video and doesn't even make a joke about it, but pauses a bit when saying it and hurries over it.
@Mode_Sierra
3 жыл бұрын
That’s such a smart observation! Love it.
I love this video! What a concise explanation of how the prop control works!
0:55 I love that sound when a king air starts! I've gotten to work on some king airs in the hangar I work at, while they're a little difficult as far as their engineering goes, they are a joy to look at, and a joy to be around. King Air is easily one of the best planes ever built.
Thanks for taking the time to show this Johan and explain what the mechanisms are doing too.
Very nice and very nerdy. Thanks for uploading and catering for those of us who like to see what goes on under the cowls, covers and access panels.
Used to love cranking up the APU on the C-141B. Sweet music to the ears.
I love the start sound ❤
@pieterpretorius1014
3 жыл бұрын
the PT6 is a nice engine to begin with
This was great to see behind the curtain a bit. Thank you 👍
This is one of the best videos that explains and shows how the props change pitch and I too love that turbine sound. The KingAir is a beautiful aircraft.
You are right, not something you get to see very often. I like that you went through the start up. Good video. Thanks for sharing.
@eugeneoreilly9356
10 ай бұрын
The Blue Max,great film.
@72Bluemax
10 ай бұрын
@@eugeneoreilly9356 nice you are the only one to make that connection. My grandfather was a Lt. Col. In the A Force and that was his call sign.
I remember on the 99's every winter rigging the reverse torque and every spring rigging them back. This was in northern Ontario where winter daytime temperatures could be below -30c.
@Mode_Sierra
3 жыл бұрын
I just know you have interesting stories as soon as you mention 99’s and Ontario Winters.
@JombieMann
3 жыл бұрын
@@Mode_Sierra I worked for Bearskin from 86 to 88. Seen plenty of 99's operating in some harsh conditions.
King Airs are so sweet. Thanks for the demo, it's fantastic.
Thanks for that demonstration. Its good to see it in real life. Keep'em coming, love the King Airs
I worked on 350’s and next will be 1900’s. In my opinion, beautiful aircraft.
Very Nice video! Completely clear, direct and didatic. Great! Hello from São Luís Maranhão Brazil!
Really interesting video. Thanks for taking us thru each step and explaining the reasoning for each.
Great demonstration!
Nice simple demo and explainations, thank you!
@Mode_Sierra
4 жыл бұрын
No problem... sometimes simpler is better hey :)
Thank you for this video!
A very good, educational video.
Although I knew almost nothing about aircraft, this vid is very interesting for me (and others alike)... Thanks for the rare demo. Be safe 🌹
Great demonstration! Thanks!
@Mode_Sierra
4 жыл бұрын
I’ll do some more some time
Great video .. never saw propeller pitch change function in action before .. good one
Makes me wish that I could have gone to pilot school. That was beautiful
@Mode_Sierra
3 жыл бұрын
Do it!
@danmanthe9335
3 жыл бұрын
I don't know what company would want to hire a pilot as old as I am. At least from the research I've done
@wowwowwiiwowiwwiwiwiwiwiwi8294
3 жыл бұрын
How old are you sir?
@danmanthe9335
3 жыл бұрын
@@wowwowwiiwowiwwiwiwiwiwiwi8294 38
@OscarScheepstra_Artemis_
3 жыл бұрын
You can always fly for a drug cartel in the middle of a jungle. :D
fascinating demonstration! your camera even enables to see the propeller pitch movements!
Awesome video!! Thanks for this!
What an awesome video,thanks!
Very interesting demonstration, Thanks
That was incredible. Very few vids that have an actual person with actual knowledge. Would love to see the inside mechanical part of pitch
Lovely demo!
Fascinating! It is interesting how those boost pumps would run, even before the battery master switch was switched on.
@Mode_Sierra
3 жыл бұрын
Yes, they are on the “hot bus” and one of the C90 “gotcha’s” to look out for. Could drain the battery regardless of battery switch position.
What a treat thank you!
Interesting! I used to fly my multiengine schoolflights at c90. Nice plane and plenty of power. You have even glass cocpit! We had steam gauges all over 😄
Thanks captain for the excellent demonstration 👌
@Mode_Sierra
2 жыл бұрын
You got it 👍🏻
That was very informative and concise, now I'm sure I can fly it! I'm interested in the mechanical linkage that alters the pitch of the propellers.
@Mode_Sierra
3 жыл бұрын
Hi, if you research “propeller governors” you’ll see how the governor works to maintain propeller RPM using engine oil.
Thanks you answered several questions I had
absolutely love this
Beautiful.
Beautiful aircraft
Great video!
Fine: pushes air, lets you fly Coarse: almost no air resistance, lets you glide
@0RespectMyAuthority0
3 жыл бұрын
The way I used to remember it is Coarse sounds like Cut, props turn into little knives in the air.
@matthiaspatzelt3085
3 жыл бұрын
Fine: pushes little air per revolution, results in higher RPM and less torque, keeping power reserves for go-around etc. Coarse: pushes more air per revolution, lower RPM, higher torque. Too much torque will damage the engine. Feather: pushes little to no air, reduces drag and allows for better glide performance in case of engine failure
@zhuzzir
3 жыл бұрын
@@matthiaspatzelt3085 thanks, sure its nothing for those who knows but means a lot for those who know nothing like me... 😅👍
@Juppie902
3 жыл бұрын
@@matthiaspatzelt3085 wait, i thought coarse is feather in props ?! because the angle of blades in feathering and in coarse results in little to no RPM
Very cool. Thanks for sharing.
perfect, thanks for this lesson :-)
This is super interesting!
I saw flames, im happy
Thank you so much!
That was fascinating 😀
Thanks For this vid !
God that is such a beautiful airplane.
@bliglum
2 жыл бұрын
Agreed, King Air is easily one of the most handsome twin prop planes ever built.
Great video instruction!
incredible video thx
Amazing!
Fascinating
Wow...that is awesome ...
Marvelous 😍
Love it!
good job
Best video I've seen to date!
@Mode_Sierra
3 жыл бұрын
True praise! I got into helicopters too in the last few years! From your profile pic, you could teach me a thing or two!
@Whirlynerds
3 жыл бұрын
@@Mode_Sierra I'm a true fan! loved helis since age 3. This is the first video I've found that answers all my questions in full, i'll be sure to check out your others ;)
@Mode_Sierra
3 жыл бұрын
@@Whirlynerds I’ve been reluctant to post more, but the response has been encouraging.
This is sooooo cooooool!
loved it
Wow! Thanks
Nice video👍
Cool vid 😎👌👍
Thanks! Cool video.....
Nice thank you
Nice one Johan
Cool. Thanks
Does the red morse cable on the port engine shown.. have too much kink behind the casing mount.. causing a cable core fray to failure point.. ???????? it might be interesting to cut the ends off a used cable and extract the cable core to check for hard spots from excessive flexing. then unwind the core strand by strand. in that area..
Very neat
Quick question, do ones require somekind of key or card to start an aircraft (ie like starting a car engine) before all those starting seq? 🙏
Fantástica tecnologia!
Very interesting indeed ! Thanks for this demonstration. I am not used to turboprops, flying only small piston engines. What about the fuel consumption during feathering ? Does it increase because of the higher resistance of the prop ?
@Mode_Sierra
4 ай бұрын
It’s neglible. Remember that the engine is never working any harder throughout the process. The “Power Levers” are never touched during the demonstration… it’s idle power throughout.
Great video! Which airport is this at?
Gracias🇲🇽
That was really interesting to watch without engine cover. One question, which may appear really minimal, but when you toggle some switches you use a thumb and forefinger movement as if "pulling" the switch. Is this a mechanism in the switch requiring to pull it out, or is just best practice so you know you've completed it?
@Mode_Sierra
3 жыл бұрын
That’s a good observation. Yes, your assumption is correct. Some switches on the panel are of the type that requires you to pull the switch before moving it. This is to avoid unintentional or accidental switching.
@Airplane_Willy
3 жыл бұрын
I agree with Johan, that was a really good observation. I tried to find a diagram of one, but couldn't. Essentially some of the King Air switches have a tooth that you have to pull the spring-loaded sleeve on the switch back over the tooth to shut it off. That is so they aren't inadvertently turned off in flight. If I find a diagram I'll come back and post it.
@PhilbyFavourites
3 жыл бұрын
@@Mode_Sierra I noticed that too. I thought with that panel down by your left hand side you could wreak havoc with just the brush of an arm. Now I know why you don’t. Thanks very much 👍🏻👍🏻
Sweet music
Interesting!
Wouldn't it be fascinating to be able to see through the whole of the engine as if it were glass and be able to observe all of the internal workings. CGI animations can provide this but they're not the "real deal", maybe in the future a material will be designed that would allow this.
Osm vdo sir i like it.. Make more vdo like this.
Thank you for showing the prop mechanism, never actually saw it in action during eight years of aviation! Gotta love pilots thinking of the community while doing those kind of tests :-) Got a question for you: Why do the boost pumps need to be on during shutdown or a least until N1 being below 10 percent? The condition levers are already in the cutoff position, why worry about boost pumps and N1?
@Mode_Sierra
3 жыл бұрын
You are welcome! Glad you liked it. Someone else asked the same question, so I’ve copied the answer. Let me know if it explains it ok. The purpose of the electric boost bumps is to prevent cavitation of the engine driven fuel pumps. Cavitation (destructive) happens when there is back pressure in the fuel flow and “bubbles” that vaporise form in the fuel pump. Cavitation can destroy your engine driven fuel pump over time. And no engine driven fuel pump means “bye bye engine”. The electric boost pump operates at a much lower pressure than the engine driven fuel pump and can’t support the required fuel pressure for the engine. It only serves to protect the engine driven pumps from cavitation damage. Above 10% The electric boost pumps still do their “job” of preventing cavitation. Once below 10% the risk of cavitation ceases and the boost pumps can be turned off. Hope that explains it ok.
Boa Noite meu amigo Donizete Bragança Paulista SP. Brasil
Props to you gaggety
Great video. Why do you wait until N1 is below 10% to shut off the boost pumps?
@Mode_Sierra
3 жыл бұрын
Hi there, the purpose of the electric boost bumps is to prevent cavitation of the engine driven fuel pumps. Cavitation (destructive) happens when there is back pressure in the fuel flow and “bubbles” that vaporise form in the fuel pump. Cavitation can destroy your engine driven fuel pump over time. And no engine driven fuel pump means “bye bye engine”. The electric boost pump operates at a much lower pressure than the engine driven fuel pump and can’t support the required fuel pressure for the engine. It only serves to protect the engine driven pumps from cavitation damage. Above 10% The electric boost pumps still do their “job” of preventing cavitation. Once below 10% the risk of cavitation ceases and the boost pumps can be turned off. Hope that explains it ok.
@Mode_Sierra
3 жыл бұрын
@@DylanClements98 Always learning! Are you related to Tom Clements?
Cool video, thanks!
0:44 Is that elbow pipe the intake or the exhaust of the turbine? The metal looks discoloured from heat, so maybe the exhaust? But that would mean the engines are put on backwards, no?
@Mode_Sierra
3 жыл бұрын
It is the exhaust. And you are right, the PT6 engine is a reverse flow turbine engine. See my anti ice demo video for more explanation :)
i allways know the sound these props make when takeing off i live 10 miles from alb int i can hear them takeing off
Oooohhh, soooo many shiny buttons!! Must... Press... Them... All....... Oh, and nice plane and start-up sound too i suppose! Haha!
Does running in the feathered position make the power turbines run hotter ? Going from fine to featherd lost you something like 65% prop RPM. Are there any drawbacks to that kind of speed loss ? Great video by the way!!
@Mode_Sierra
Жыл бұрын
In my experience the turbines might run slightly hotter but totally negligible. To me, the benefits of starting with the props feathered outweigh the disadvantages. Things like: Quieter, friendlier to ramp personnel, if there is snow/ice etc… inadvertent taxying if the parking brake loses pressure etc.
@paulhatfield498
Жыл бұрын
@@Mode_Sierra hey mate. Super interesting. Not a pilot but fascinated by these machines. I do volunteer ambulance work in a remote community in Western Australia. We transfer patients to the local airport and its most often a PC12 that picks them up. Spool up time is so fast on these things. I fly RC jets and our miniature turbines take longer to start than a pt6.
Hey, what do you use what prop setting for? Heard it’s like shifting gears(?) do you use the low angle of attack of the prop-blades for acceleration then and the high angle of attack once you’re in a faster cruise flight, like an overdrive gear? I’d love to hear from you, since I’ve never operated any plane that used an adjustable prop! 😄
@lancelotvt
3 жыл бұрын
Fine pitch on the blades to achieve a higher RPM to increase climb performance at lower altitudes where the air is more dense. Once the aircraft is level at altitude feathering the props allows the blades to more effectively "bite" in to the less dense air increasing engine efficiency.
@Mode_Sierra
3 жыл бұрын
In essence, regarding prop lever settings, the only pilot action during a “normal” flight in this type of aircraft is as follows: -Props full forward (fine pitch) for taxi and Take Off. See Note 1 below. -Adjust the props to “Maximum Continuous RPM, or Climb RPM shortly after take off. See Note 2 below. -Reduce Prop RPM for the cruise. See Note 3 Below -During the approach phase adjust your props back full forward for the landing (reverse thrust) or for the anticipated “go around”. See Note 4 Below. That’s it. The rest of the time, the governor works to achieve the RPM that the pilot has “asked for”/selected. So when there is excess power, it simply reduces the pitch of the blades to take a bigger “bite” of the air. Notes. Note 1: The props won’t achieve the High RPM you require, until you apply sufficient power using the power (thrust) levers to turn them fast enough. Once you have enough (and excessive) power, the governor will continuously adjust the propeller pitch to maintain the RPM you requested. Note 2: In the C90GTX, the difference between Maximum RPM (time limited) and Maximum Continuous RPM is very small. Just a fine tickle back of the prop levers. If the props are rigged correctly, this is a change of 1,926 RPM to 1,900 RPM. In other King Air models, the difference between Max RPM and Max Continuous is more of an adjustment. (300-400 RPM in the in the models I’ve flown) Note 3: Refer to the Cruise Tables in your Pilot Operating Handbook. In this particular model, you can leave the props at 1,900. We do however tend to adjust them to 1,800 for longer cruises, because it changes the “tone” of the props to a more comfortable one for passenger comfort. Note 4: Pilot technique differs here, based on the types of props you have fitted, runway available and passenger comfort. In the C90GTX, I always adjust the Props to full forward in the final approach phases of a flight. That way, the “Reverse Thrust” is ready on the ground and I simply have to put the power levers in reverse. Same with a go-around... it leaves me less things to do. In the B200 or other models of the 90 that I’ve flown, you could be adjusting the props from 1,600 to 2,200 RPM ready for the reverse or go around. This can have quite a noise increase for passengers. So, many pilot choose to leave the props where they are until after touchdown, when they will then whack prop levers full forward before applying reverse thrust. This of course, is runway length and other conditions permitting. I know this is a long reply, so I’m going to add it to the description of the video. Hope it helps.
@sioul2006
3 жыл бұрын
@@Mode_Sierra Man, this helped for sure! I really appreciate your effort to response so detailed! I’m not very experienced yet, mostly flew sailplanes and once in a while single engine piston‘s with non-adjustable props. There’s always something new to learn every day. It seems a little complex, looking for the prop setting as well, but I’m pretty sure once you get used to it it won’t be a problem at all. Thanks again for the long reply, I really enjoyed reading this and it helped me a lot! :)
@sioul2006
3 жыл бұрын
@@lancelotvt Thank you very much this helped me get a general understanding very much! :)
You can either buy it part by or buy plane and a business jet have 2 different motor for flight
Question: How short can a King Air takes off let's say at an airfield with 25 feet MSL elevation and an OAT of 30°C, wind calm? And can it takeoff from a grass runway?
@Mode_Sierra
2 жыл бұрын
Without getting the POH out, I can tell you that I have many times taken the C90GTX into and out of a grass airfield that is 800 meters long. Max 4 occupants and 1,400lbs of fuel. That’s just over two hours endurance.
@09shadowjet
2 жыл бұрын
@@Mode_Sierra thank you for the answer! It's quite a versatile plane yeah?