Rick Stitt strikes again... Please Read.

.....from R.L. Darling


Mr. Chitwood,

I have been following Rick Stitts misadventures for over a year now.
I have a RotorWay Exec and a Helicycle helicopter and have two friends
with Mini-500's that have the Stitt touch on them. One has had the
re-built cones and transmission and the other has the tranny mods
done.

The first clue we had of improper work was the cones...so sloppy I
refused to help the owner reinstall them on the aircraft...then his
"re-built trans" locked up. Upon dissassembly , we found the
bearings
to be thickly encrusted with rust as if they had been submerged in
salt
water for many years.

The other ship has been grounded and I won't know the extent of the
damage untill I have a chance to tear it down and inspect it closely.

The first ships owner is Mr. Wayne Qualls....he is a knowledgeable
pilot
and has done his own turbine conversion which has proved successful.
I
know that he would like to talk to you about Mr. Stitts so he won't
mind
if I let you have his phone number....he too has been bamboozled out
of
thousands of dollars that he can not afford.

The number is xxxxxxxxxxx...this is in Irving, Texas and believe
me....he will welcome your call. I can personally vouch that he
sent
the parts to Mr. Stitts and personally inspected the trans, and
bearings
after it locked up ...the tranny had less than 15 minutes on it as it
sat
in the hanger , unused-full of oil- for several months. I too am in
belief that if any of these modified Mini-500's are allowed to fly
that
we will have multiple fatalities.

Please give him a call.....

Thanks for keeping people informed...

R.L. Darling
Dallas, Texas

Thanks for the incoming comments. We need to stop this guy before
people start dying again. Stitt's turbine startup sequence is WAY
wrong. His method will cost you $$$$$ in turbines , as his method
guarantees hot starts, or a least unnecessary high temps.
D. Chitwood
N500XT

Thanks for the incoming comments. We need to stop this guy before
people start dying again. Stitt's turbine startup sequence is WAY
wrong. His method will cost you $$$$$ in turbines , as his method
guarantees hot starts, or a least unnecessary high temps.
D. Chitwood
N500XT


Student, and a beginner here...still learning about pistons, but
I've seen this term before here...Please explain 'hot starts'.


Thanks.

p

OT to R.L Darling: How is your Helicycle doing?? I saw it at
Waxahatchee...Stu Fields
"Dennis Chitwood" wrote in message
om...
....from R.L. Darling


Mr. Chitwood,

I have been following Rick Stitts misadventures for over a year now.
I have a RotorWay Exec and a Helicycle helicopter and have two friends
with Mini-500's that have the Stitt touch on them. One has had the
re-built cones and transmission and the other has the tranny mods
done.

The first clue we had of improper work was the cones...so sloppy I
refused to help the owner reinstall them on the aircraft...then his
"re-built trans" locked up. Upon dissassembly , we found the
bearings
to be thickly encrusted with rust as if they had been submerged in
salt
water for many years.

The other ship has been grounded and I won't know the extent of the
damage untill I have a chance to tear it down and inspect it closely.

The first ships owner is Mr. Wayne Qualls....he is a knowledgeable
pilot
and has done his own turbine conversion which has proved successful.
I
know that he would like to talk to you about Mr. Stitts so he won't
mind
if I let you have his phone number....he too has been bamboozled out
of
thousands of dollars that he can not afford.

The number is xxxxxxxxxxx...this is in Irving, Texas and believe
me....he will welcome your call. I can personally vouch that he
sent
the parts to Mr. Stitts and personally inspected the trans, and
bearings
after it locked up ...the tranny had less than 15 minutes on it as it
sat
in the hanger , unused-full of oil- for several months. I too am in
belief that if any of these modified Mini-500's are allowed to fly
that
we will have multiple fatalities.

Please give him a call.....

Thanks for keeping people informed...

R.L. Darling
Dallas, Texas

Thanks for the incoming comments. We need to stop this guy before
people start dying again. Stitt's turbine startup sequence is WAY
wrong. His method will cost you $$$$$ in turbines , as his method
guarantees hot starts, or a least unnecessary high temps.
D. Chitwood
N500XT

"Peter Maus" wrote in message
Student, and a beginner here...still learning about pistons, but
I've seen this term before here...Please explain 'hot starts'.

It is a turbine only term, there is no piston engine equivalent. It is when
there is too much fuel in the engine or too little air moving through it.


Now, for the thorough explanation...

Here is a basic distinction between gas turbines and piston engines- piston
engines normally use the right amount of air for how much fuel they use.
Gas turbines almost always use excess air, sometimes two or three times as
much as necessary to burn the fuel. This extra air makes the flame
temperature several hundred degrees cooler.


In general terms, here is how a gas turbine engine normally starts:

1)
First, a starter turns the compressor, accelerating it from zero speed.

2)
Ignitors (like spark plugs) fire whenever the starter is turning in most
engine designs, and usually once or two sparks per second.

3)
Next, above some designated rpm, an exact flow of fuel is introduced. This
sprays near the ignitors and usually the flame starts within a few seconds.

4)
After the flame starts, the rpm will accelerate even more than with the
starter only.

5)
Above some designated rpm, approximately idle speed, the starter is not
used. It may be disengaged, power removed from it, and either automatically
or by the pilot flipping a switch (depending on which design).

6)
The engine is now at idle speed (usually above 50% rpm) after a normal
start.

A hot start may occur for a few main reasons:

A weak starter may not turn the engine fast enough. Between (4) and (5),
both the flame and starter are required to accelerate the engine to idle
speed. With the starter only, the engine can turn up to around 25% of
maximum rpm. Without the starter but the flame only, the engine can run at
any speed as long as it does not drop below around 40-50% rpm. If it drops
below that it will not be able to recover speed eventually stop. So... if
the starter is weak, or it drops out at too low an rpm (5), then the engine
will not be able to reach idle speed. This is like a car that will almost
start but sputters and dies instead. The difference with the gas turbine is
that fuel will keep on coming and burning as a turbine winds down over the
next several seconds, and may then burn too hot. The engine may also "hang"
at an rpm below idle with the flame temperature otherwise acceptable, but
that is called a "hung start," not "hot start." Air starters may be weak
from too little air spinning them or from being worn out. Electric starters
may also wear out, or be weak from a weak aircraft battery just like a car.
The oil in the engine may also be cold and thick, which requires a stronger
starter.

The fuel may be turned on too early (3), before the engine is turning fast
enough and moving enough air through the engine. So not enough air means
too hot a flame.

The fuel may take too long ignite even if everything else is functioning
correctly (2,3,4). The unlit fuel can collect in the engine over several
seconds, then ignite all at once. So too much fuel means too hot a flame.
Sometimes the flame may go all the way out the exhaust pipe like the
Batmobile, this is referred to as "torching."

The engine may malfunction and spray use too much fuel during a start (3).

Lastly, the engine may still be hot if it was just running. In this case,
you simply have to run the starter for a little longer to blow fresh air
through the engine to cool it off before turning on the fuel.



So I hope that makes sense. I simplified most of the explanation, tried to
make all the theory relevant but provide some real day-to-day examples of
causes. Still, it is all more or less true for all gas turbine engines.

Jim Carriere wrote:

"Peter Maus" wrote in message
Student, and a beginner here...still learning about pistons,... but
I've seen this term before here...Please explain 'hot starts'.

It is a turbine only term, there is no piston engine equivalent.



Yes, I realize that. But it comes up so often in my reading. I'm
curious, and have not found reasonable explanations.






It is when
there is too much fuel in the engine or too little air moving through it.

Now, for the thorough explanation...

Here is a basic distinction between gas turbines and piston engines- piston
engines normally use the right amount of air for how much fuel they use.
Gas turbines almost always use excess air, sometimes two or three times as
much as necessary to burn the fuel. This extra air makes the flame
temperature several hundred degrees cooler.





Ok. I'm with you, there. Diesels are non stoichiometric as well.
Although I wouldn't want to fly one.



In general terms, here is how a gas turbine engine normally starts:

1)
First, a starter turns the compressor, accelerating it from zero speed.

2)
Ignitors (like spark plugs) fire whenever the starter is turning in most
engine designs, and usually once or two sparks per second.

3)
Next, above some designated rpm, an exact flow of fuel is introduced. This
sprays near the ignitors and usually the flame starts within a few seconds.

4)
After the flame starts, the rpm will accelerate even more than with the
starter only.

5)
Above some designated rpm, approximately idle speed, the starter is not
used. It may be disengaged, power removed from it, and either automatically
or by the pilot flipping a switch (depending on which design).

6)
The engine is now at idle speed (usually above 50% rpm) after a normal
start.

A hot start may occur for a few main reasons:

A weak starter may not turn the engine fast enough. Between (4) and (5),
both the flame and starter are required to accelerate the engine to idle
speed. With the starter only, the engine can turn up to around 25% of
maximum rpm. Without the starter but the flame only, the engine can run at
any speed as long as it does not drop below around 40-50% rpm. If it drops
below that it will not be able to recover speed eventually stop. So... if
the starter is weak, or it drops out at too low an rpm (5), then the engine
will not be able to reach idle speed. This is like a car that will almost
start but sputters and dies instead. The difference with the gas turbine is
that fuel will keep on coming and burning as a turbine winds down over the
next several seconds, and may then burn too hot. The engine may also "hang"
at an rpm below idle with the flame temperature otherwise acceptable, but
that is called a "hung start," not "hot start." Air starters may be weak
from too little air spinning them or from being worn out. Electric starters
may also wear out, or be weak from a weak aircraft battery just like a car.
The oil in the engine may also be cold and thick, which requires a stronger
starter.

The fuel may be turned on too early (3), before the engine is turning fast
enough and moving enough air through the engine. So not enough air means
too hot a flame.

The fuel may take too long ignite even if everything else is functioning
correctly (2,3,4). The unlit fuel can collect in the engine over several
seconds, then ignite all at once. So too much fuel means too hot a flame.
Sometimes the flame may go all the way out the exhaust pipe like the
Batmobile, this is referred to as "torching."

The engine may malfunction and spray use too much fuel during a start (3).

Lastly, the engine may still be hot if it was just running. In this case,
you simply have to run the starter for a little longer to blow fresh air
through the engine to cool it off before turning on the fuel.

So I hope that makes sense. I simplified most of the explanation, tried to
make all the theory relevant but provide some real day-to-day examples of
causes. Still, it is all more or less true for all gas turbine engines.



Thank you. You've been very helpful. This clarifies a lot.


Much obliged.


p

A "hot start" is where you give the turbine engine too much fuel too
soon during the start up or there is fuel left in the engine after the
previous shutdown. The power turbine wheel over heats. If the EGT
temperature goes past read line then the turbine wheel and other
expensive parts MUST be replaced or sometime in the not too distant
future the turbine wheel will come apart rapidly. If the hot start is
bad enough and exceeds red line it can cost $50K- $1M+ for the engine
tear down and parts replacement.

On Sun, 04 Jan 2004 03:41:11 GMT, Peter Maus
wrote:



Thanks for the incoming comments. We need to stop this guy before
people start dying again. Stitt's turbine startup sequence is WAY
wrong. His method will cost you $$$$$ in turbines , as his method
guarantees hot starts, or a least unnecessary high temps.
D. Chitwood
N500XT


Student, and a beginner here...still learning about pistons, but
I've seen this term before here...Please explain 'hot starts'.


Thanks.

p

"Jim Carriere" wrote in message ...
"Peter Maus" wrote in message
Student, and a beginner here...still learning about pistons, but
I've seen this term before here...Please explain 'hot starts'.

It is a turbine only term, there is no piston engine equivalent. It is when
there is too much fuel in the engine or too little air moving through it.


Hold on for a minute.......
It is not a turbine only term! Look in any number of piston engine
manuals and especially with fuel injection for "HOT START PROCEDURES".
It happens generally with high ambient temperatures when the fuel air
mixture ratio is not correct or normal. Each engine will require
different procedures according to the manufacturer.
Your description for turbines is essentially correct across the board
but to say its only for turbines is not correct.
Ol Shy & Bashful


Now, for the thorough explanation...

Here is a basic distinction between gas turbines and piston engines- piston
engines normally use the right amount of air for how much fuel they use.
Gas turbines almost always use excess air, sometimes two or three times as
much as necessary to burn the fuel. This extra air makes the flame
temperature several hundred degrees cooler.


In general terms, here is how a gas turbine engine normally starts:

1)
First, a starter turns the compressor, accelerating it from zero speed.

2)
Ignitors (like spark plugs) fire whenever the starter is turning in most
engine designs, and usually once or two sparks per second.

3)
Next, above some designated rpm, an exact flow of fuel is introduced. This
sprays near the ignitors and usually the flame starts within a few seconds.

4)
After the flame starts, the rpm will accelerate even more than with the
starter only.

5)
Above some designated rpm, approximately idle speed, the starter is not
used. It may be disengaged, power removed from it, and either automatically
or by the pilot flipping a switch (depending on which design).

6)
The engine is now at idle speed (usually above 50% rpm) after a normal
start.

A hot start may occur for a few main reasons:

A weak starter may not turn the engine fast enough. Between (4) and (5),
both the flame and starter are required to accelerate the engine to idle
speed. With the starter only, the engine can turn up to around 25% of
maximum rpm. Without the starter but the flame only, the engine can run at
any speed as long as it does not drop below around 40-50% rpm. If it drops
below that it will not be able to recover speed eventually stop. So... if
the starter is weak, or it drops out at too low an rpm (5), then the engine
will not be able to reach idle speed. This is like a car that will almost
start but sputters and dies instead. The difference with the gas turbine is
that fuel will keep on coming and burning as a turbine winds down over the
next several seconds, and may then burn too hot. The engine may also "hang"
at an rpm below idle with the flame temperature otherwise acceptable, but
that is called a "hung start," not "hot start." Air starters may be weak
from too little air spinning them or from being worn out. Electric starters
may also wear out, or be weak from a weak aircraft battery just like a car.
The oil in the engine may also be cold and thick, which requires a stronger
starter.

The fuel may be turned on too early (3), before the engine is turning fast
enough and moving enough air through the engine. So not enough air means
too hot a flame.

The fuel may take too long ignite even if everything else is functioning
correctly (2,3,4). The unlit fuel can collect in the engine over several
seconds, then ignite all at once. So too much fuel means too hot a flame.
Sometimes the flame may go all the way out the exhaust pipe like the
Batmobile, this is referred to as "torching."

The engine may malfunction and spray use too much fuel during a start (3).

Lastly, the engine may still be hot if it was just running. In this case,
you simply have to run the starter for a little longer to blow fresh air
through the engine to cool it off before turning on the fuel.



So I hope that makes sense. I simplified most of the explanation, tried to
make all the theory relevant but provide some real day-to-day examples of
causes. Still, it is all more or less true for all gas turbine engines.

"Rocky" wrote in message
Hold on for a minute.......
It is not a turbine only term! Look in any number of piston engine
manuals and especially with fuel injection for "HOT START PROCEDURES".
It happens generally with high ambient temperatures when the fuel air
mixture ratio is not correct or normal. Each engine will require
different procedures according to the manufacturer.

OK, I didn't think of that. I have very little piston time- in aircraft
anyway...

This is the same term for for apples and oranges though. In a turbine hot
start the risk is damaging the engine. In a piston hot start the risks is
not starting, right? Like flooding a car engine on a hot summer day, or did
I get the wrong idea?

Anyway, you learn something new every day, and I'm glad my explanation made
sense to Peter Maus.

"Jim Carriere" wrote in message ...
"Rocky" wrote in message
Hold on for a minute.......
It is not a turbine only term! Look in any number of piston engine
manuals and especially with fuel injection for "HOT START PROCEDURES".
It happens generally with high ambient temperatures when the fuel air
mixture ratio is not correct or normal. Each engine will require
different procedures according to the manufacturer.

OK, I didn't think of that. I have very little piston time- in aircraft
anyway...

This is the same term for for apples and oranges though. In a turbine hot
start the risk is damaging the engine. In a piston hot start the risks is
not starting, right? Like flooding a car engine on a hot summer day, or did
I get the wrong idea?

Anyway, you learn something new every day, and I'm glad my explanation made
sense to Peter Maus.

Jim
As I said, your explanation was essentially good across the board for
turbines and I couldn't have said it better . I've seen some awesome
examples of hot starts with turbine and one that resulted in a rapid
meltdown of a PT6. I'm glad it wasn't me with my finger on the start!!
Most generally the flawed hot start with piston can result in a dead
battery, or burning up a starter. I've seen at least one fire started
with a starter that got overheated and ignited wires and insulation.
In any case, its wise to know the correct procedures for each and
important to follow them!
Cheers
Flyinrock

"HOT START" for a turbine engine refers to when DURING the start the maximum
turbine inlet temperature has been exceeded. Subsequent inspection is
required prior to flight. In a piston engine a HOT START PROCEDURE tells
you how to start an already hot engine as when you just shut down and are
restarting...like maybe don't pull the choke? The terms for turbins and
piston engines are not comparable.

Bob