turbine boat question??

the really loud screeching at idle is from the bleed band being wide openreducing the air into the combustion chamber so as to not blow the flame out the more power a turbine makes the quieter it gets as all the air is forced thru the engine... some of the sounds you hear docking are there is a large disk brake on the output shaft with often 2 calipers they use a trim pump for brake pressure and can stop the n2 or power turbine to shift when released it sounds like blowing compressed air on a bearing as the blades spin up to speed.....all the blades in a turbine are hollow and have air blowing thru them to cool them thats what a hot start is to big of fire with not enough cooling air inside the blades then they can melt or bend with not good results!

Yes and no

The Bleed band closes at approx 85 percent n1.

Do you know what happens if it closes too late?

Here is the compressor section before balancing
also pictured is a set of Stainless compressor housings.
These were designed for salt water application for the navy.
 

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Now take this killer equipment and come to a race course no matter the conditions. Sit in a milling area for 20 min while 2-3 of the fastest turbine raceboats in the world and 3-4 of the fastest Piston boats circle around you all wanting to be king, intimidation moves , cutoff here, a little bump there , it's getting hot . smoke get her on plane...watch out...did he just cut us off......fkn d**k. Green green green Go Go go go
Hold the 3800 hp wide open for two miles or whenever you've scared the crap out of yourself (175 or so 2-4's is usual) and don't get pinched turn one coming easy easy... turn as fast as you possibly can without flipping the boat over. Pin it and hold for 1.5 miles over what is probably a quartering sea (don't miss a throttle an over speed will cost the team 100+ k) ...as fast as 3800 hp wll take you (Watch the boat 10 feet away next to you at the same speed) Another turn ..back down to 135 anything more and your swimming...ahhh flat water ahead after this little hole by the jetty....but a nasty dog leg with race boat wakes to turn on...concrete to your right ...please don't hook. Hold it down....como'n faster 150, 160,165 ...turn..easy...hold it...turn easy little more...straight ...Hold it hard into the harbor. Concrete post to the starboard Hair-pin ahead ..... All system down (Bleed bands Popping off like fire crackkers)... ready Turn Turn turn..Nail it .....Wide open Pinned

You have 11 more laps to go.. Welcome to Key west in a turbine boat :driving:
 
Some turbines can't be stalled at all. The Lycoming is tolerant of it, but not for any great amount at time and only at idle speed. Idle speed is sort of a funny term- Idle on a turbine is only about 20% less than max RPM. At that speed, it's not putting enough energy into the N2 stage to move it very fast.


John Arruda would pop in here now and again- he's obviously way more knowledgeable on this stuff. Hopefully he sees this.

The ground idle is set at anywhere between 45-55 percent n1.
N1 max rpm is 105 percent.
 
Throttling which (n1 or n2) provides better throttle response?

Logically, I would think acceleration wise..throttling N2.. it would be like a clutch, if N1 is making the power, you are applying the power to N2. That would seem to be faster than increasing the power of N1 and applying it to N2. If your car is taking 4 grand and you dump the clutch your going to launch harder than stepping on the gas from idle.
 
Now take this killer equipment and come to a race course no matter the conditions. Sit in a milling area for 20 min while 2-3 of the fastest turbine raceboats in the world and 3-4 of the fastest Piston boats circle around you all wanting to be king, intimidation moves , cutoff here, a little bump there , it's getting hot . smoke get her on plane...watch out...did he just cut us off......fkn d**k. Green green green Go Go go go
Hold the 3800 hp wide open for two miles or whenever you've scared the crap out of yourself (175 or so 2-4's is usual) and don't get pinched turn one coming easy easy... turn as fast as you possibly can without flipping the boat over. Pin it and hold for 1.5 miles over what is probably a quartering sea (don't miss a throttle an over speed will cost the team 100+ k) ...as fast as 3800 hp wll take you (Watch the boat 10 feet away next to you at the same speed) Another turn ..back down to 135 anything more and your swimming...ahhh flat water ahead after this little hole by the jetty....but a nasty dog leg with race boat wakes to turn on...concrete to your right ...please don't hook. Hold it down....como'n faster 150, 160,165 ...turn..easy...hold it...turn easy little more...straight ...Hold it hard into the harbor. Concrete post to the starboard Hair-pin ahead ..... All system down (Bleed bands Popping off like fire crackkers)... ready Turn Turn turn..Nail it .....Wide open Pinned

You have 11 more laps to go.. Welcome to Key west in a turbine boat :driving:

F$kin Aye bro thats the sh@t right there:sifone:
 
Logically, I would think acceleration wise..throttling N2.. it would be like a clutch, if N1 is making the power, you are applying the power to N2. That would seem to be faster than increasing the power of N1 and applying it to N2. If your car is taking 4 grand and you dump the clutch your going to launch harder than stepping on the gas from idle.

Most Turbine installs do not do this.
 
Now take this killer equipment and come to a race course no matter the conditions. Sit in a milling area for 20 min while 2-3 of the fastest turbine raceboats in the world and 3-4 of the fastest Piston boats circle around you all wanting to be king, intimidation moves , cutoff here, a little bump there , it's getting hot . smoke get her on plane...watch out...did he just cut us off......fkn d**k. Green green green Go Go go go
Hold the 3800 hp wide open for two miles or whenever you've scared the crap out of yourself (175 or so 2-4's is usual) and don't get pinched turn one coming easy easy... turn as fast as you possibly can without flipping the boat over. Pin it and hold for 1.5 miles over what is probably a quartering sea (don't miss a throttle an over speed will cost the team 100+ k) ...as fast as 3800 hp wll take you (Watch the boat 10 feet away next to you at the same speed) Another turn ..back down to 135 anything more and your swimming...ahhh flat water ahead after this little hole by the jetty....but a nasty dog leg with race boat wakes to turn on...concrete to your right ...please don't hook. Hold it down....como'n faster 150, 160,165 ...turn..easy...hold it...turn easy little more...straight ...Hold it hard into the harbor. Concrete post to the starboard Hair-pin ahead ..... All system down (Bleed bands Popping off like fire crackkers)... ready Turn Turn turn..Nail it .....Wide open Pinned

You have 11 more laps to go.. Welcome to Key west in a turbine boat :driving:

Can I ask some top secret questions?
How many throttles do you have?
One per motor right?
Your n2 is wide open locked right?
 
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the n2 is reduced with this planetary reduction assembly.
This is internal in the 53 it takes the output of the n2 down to 6600rpm max.
The 55 reduction is not internal in its attended application. (chinook)
Its original gearbox is useless for a boat.
This why I asked the phenomena guys what they were using.
 

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I'm about to go back and read all 61+ pages of your Turbine 101 thread! Keep it coming!!

You may have to wipe the dust off it:)

Here is one of the fuel rails being pattern tested.
In a 53 there is 22 of them.
They have two stages each. primary and secondary
 

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So how do you throttle the n2 . I understand the brake for nuetral shift control but the throttling you kind of lost me.

Also what is the life span of the planetarys and what do they run in for lubrication?
 
i have opened a few t53s up and there is nothing to control n2 inside the engine the most basic way to describe a turbine gas producer is its a big blowtorch.....n1 and n2 control levers are strickly in the fuel control system? how does n2lever govern n2 speed? does it cut fuel or open bleed band? my brother is maintaince head at a power plant with 4 ge over 1 million hp gas turbines they are big and fasinating inside also helping a freind restore a few migs those engines are shakers you can grab the first row of blades and they are very loose and sound like wind chimes as it rotates at slow speed they lock in with centrifical force still does not seem right!
 
So how do you throttle the n2 . I understand the brake for nuetral shift control but the throttling you kind of lost me.

Also what is the life span of the planetarys and what do they run in for lubrication?

There have been several changes over the years modifying the planetarys
according to the Military manual 5000 hours.

The entire lubrication system is a dry sump system.
the oil I use is Mobil Jet.

The N2 is not throttled but rather locked into position.

I run approx 12 of these in my system.
 

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