GO480

[Mike Rapoport]

When I read about Lycoming engines the terms "wide deck", "narrow deck",
"straight valve" and angle valve are used to describe different
cylinder/case configurations. What is the GO480 in my Helio Courier?
Narrow deck? Wide deck? Angle valve? Straight valve?

Thanks

Mike
MU-2

[Margy]

Mike Rapoport wrote:
> When I read about Lycoming engines the terms "wide deck", "narrow deck",
> "straight valve" and angle valve are used to describe different
> cylinder/case configurations. What is the GO480 in my Helio Courier?
> Narrow deck? Wide deck? Angle valve? Straight valve?

The deck refers to the flange where the cylinder meets the case.
The valves straight/angle indicate whether the two rockers are
parallel to each other or form a sort of V). I don't know about
the deck, but I think the Gopher's were all angle-valve. The
wide deck engine serial numbers end in "A".

Intresting information about all this can be obtained at
www.sacskyranch.com.

My condolences on having the gopher80. Getting rid of mine
was a big improvement on the Navion.

-Ron

[George Patterson]

Margy wrote:
>
> My condolences on having the gopher80. Getting rid of mine
> was a big improvement on the Navion.

Yeah, but it took you nearly two years, didn't it?

George Patterson
Why do men's hearts beat faster, knees get weak, throats become dry,
and they think irrationally when a woman wears leather clothing?
Because she smells like a new truck.

[Margy]

George Patterson wrote:
> Margy wrote:
>
>>
>> My condolences on having the gopher80. Getting rid of mine
>> was a big improvement on the Navion.
>
>
> Yeah, but it took you nearly two years, didn't it?
>
> George Patterson
> Why do men's hearts beat faster, knees get weak, throats become dry,
> and they think irrationally when a woman wears leather clothing?
> Because she smells like a new truck.
More than that, but we got into a bad case of the "might as wells"

Margy

[Jim Burns]

If you look at the cylinder bases you can tell if it is a wide or narrow
deck.
Narrow deck engines use interior hex nuts and possibly hold down plates to
hold the cylinder to the case. Wide deck engines have studs, regular hex
nuts, and thicker cylinder flanges holding the cylinders to the case.
Wide deck engines serial numbers end in "A", narrow deck engines serial
numbers do not.
Narrow deck engines are typically older, mid-60's and earlier.

I believe that
http://www.lycoming.textron.com/support/publications/maintenancePublications/serviceInstructions/SI1037M.pdf

shows your cylinder Assembly number to contain an "r" indicating angle
valves (not parallel) and an "e" indicating needing long reach spark plugs.

Jim


"Mike Rapoport" > wrote in message
ink.net...
> When I read about Lycoming engines the terms "wide deck", "narrow deck",
> "straight valve" and angle valve are used to describe different
> cylinder/case configurations. What is the GO480 in my Helio Courier?
> Narrow deck? Wide deck? Angle valve? Straight valve?
>
> Thanks
>
> Mike
> MU-2
>
>

[Mike Rapoport]

"Margy" > wrote in message
...
> Mike Rapoport wrote:
>> When I read about Lycoming engines the terms "wide deck", "narrow deck",
>> "straight valve" and angle valve are used to describe different
>> cylinder/case configurations. What is the GO480 in my Helio Courier?
>> Narrow deck? Wide deck? Angle valve? Straight valve?
>
> The deck refers to the flange where the cylinder meets the case.
> The valves straight/angle indicate whether the two rockers are
> parallel to each other or form a sort of V). I don't know about
> the deck, but I think the Gopher's were all angle-valve. The
> wide deck engine serial numbers end in "A".
>
> Intresting information about all this can be obtained at
> www.sacskyranch.com.
>
> My condolences on having the gopher80. Getting rid of mine
> was a big improvement on the Navion.
>
> -Ron

What was the problem with the GO480? In the Helio, it is considered much
better than the TIO540 or the IO720.

Mike
MU-2

[Mike Rapoport]

Thanks Jim! I will have a look today.

Mike
MU-2

"Jim Burns" > wrote in message
...
> If you look at the cylinder bases you can tell if it is a wide or narrow
> deck.
> Narrow deck engines use interior hex nuts and possibly hold down plates to
> hold the cylinder to the case. Wide deck engines have studs, regular hex
> nuts, and thicker cylinder flanges holding the cylinders to the case.
> Wide deck engines serial numbers end in "A", narrow deck engines serial
> numbers do not.
> Narrow deck engines are typically older, mid-60's and earlier.
>
> I believe that
> http://www.lycoming.textron.com/support/publications/maintenancePublications/serviceInstructions/SI1037M.pdf
>
> shows your cylinder Assembly number to contain an "r" indicating angle
> valves (not parallel) and an "e" indicating needing long reach spark
> plugs.
>
> Jim
>
>
> "Mike Rapoport" > wrote in message
> ink.net...
>> When I read about Lycoming engines the terms "wide deck", "narrow deck",
>> "straight valve" and angle valve are used to describe different
>> cylinder/case configurations. What is the GO480 in my Helio Courier?
>> Narrow deck? Wide deck? Angle valve? Straight valve?
>>
>> Thanks
>>
>> Mike
>> MU-2
>>
>>
>
>

[Orval Fairbairn]

In article >,
"Jim Burns" > wrote:

> If you look at the cylinder bases you can tell if it is a wide or narrow
> deck.
> Narrow deck engines use interior hex nuts and possibly hold down plates to
> hold the cylinder to the case. Wide deck engines have studs, regular hex
> nuts, and thicker cylinder flanges holding the cylinders to the case.
> Wide deck engines serial numbers end in "A", narrow deck engines serial
> numbers do not.
> Narrow deck engines are typically older, mid-60's and earlier.
>
> I believe that
> http://www.lycoming.textron.com/support/publications/maintenancePublications/s
> erviceInstructions/SI1037M.pdf
>
> shows your cylinder Assembly number to contain an "r" indicating angle
> valves (not parallel) and an "e" indicating needing long reach spark plugs.
>
> Jim
>
>
> "Mike Rapoport" > wrote in message
> ink.net...
> > When I read about Lycoming engines the terms "wide deck", "narrow deck",
> > "straight valve" and angle valve are used to describe different
> > cylinder/case configurations. What is the GO480 in my Helio Courier?
> > Narrow deck? Wide deck? Angle valve? Straight valve?

Parallel-valve Lycomings have rocker covers that have parallel sides; on
angle-valve Lycomings, the sides of the rocker covers angle toward an
apex somewhere above the cylinder.

I lost a friend last year when his GO-480 threw a rod in his Pilatus
P-3. He hit a tree attempting to make an emergency landing.

--
Remove _'s from email address to talk to me.

[Ron Natalie]

Mike Rapoport wrote:

>
> What was the problem with the GO480? In the Helio, it is considered much
> better than the TIO540 or the IO720.
>
>
The thing is obsolete. Lycoming practically denies having made it (they
do deny having made the Gopher35). The TBO and Overhaul costs will kill
you. The accessories are unobtainable in many cases.

[Jim Burns]

Mike,

Just a few questions and thoughts, mainly because I'm curious.

I'd be interested to know the HP rating of the GO480 installed in the Helio.
I've been watching a few people that are building Bearhawks and one article
mentions that the GO480 isn't favored for that application for the relative
high weight to HP ratio compared to the 540.

I "believe" that the Beech Queen Air originally used a version of the 480
and I "know" a lot of them have been retrofitted with either 720's or
turbines. Whether this was due to high rebuild or maintenance costs or lack
of power, I have no idea.

Would the desirability of the 480 in the Helio be due to a desire to keep
them "original"?

Jim


"Mike Rapoport" > wrote in message
ink.net...
>
> "Margy" > wrote in message
> ...
> > Mike Rapoport wrote:
> >> When I read about Lycoming engines the terms "wide deck", "narrow
deck",
> >> "straight valve" and angle valve are used to describe different
> >> cylinder/case configurations. What is the GO480 in my Helio Courier?
> >> Narrow deck? Wide deck? Angle valve? Straight valve?
> >
> > The deck refers to the flange where the cylinder meets the case.
> > The valves straight/angle indicate whether the two rockers are
> > parallel to each other or form a sort of V). I don't know about
> > the deck, but I think the Gopher's were all angle-valve. The
> > wide deck engine serial numbers end in "A".
> >
> > Intresting information about all this can be obtained at
> > www.sacskyranch.com.
> >
> > My condolences on having the gopher80. Getting rid of mine
> > was a big improvement on the Navion.
> >
> > -Ron
>
> What was the problem with the GO480? In the Helio, it is considered much
> better than the TIO540 or the IO720.
>
> Mike
> MU-2
>
>

[Mike Rapoport]

"Jim Burns" > wrote in message
...
> Mike,
>
> Just a few questions and thoughts, mainly because I'm curious.
>
> I'd be interested to know the HP rating of the GO480 installed in the
> Helio.
> I've been watching a few people that are building Bearhawks and one
> article
> mentions that the GO480 isn't favored for that application for the
> relative
> high weight to HP ratio compared to the 540.

295HP

>
> I "believe" that the Beech Queen Air originally used a version of the 480
> and I "know" a lot of them have been retrofitted with either 720's or
> turbines. Whether this was due to high rebuild or maintenance costs or
> lack
> of power, I have no idea.
>
> Would the desirability of the 480 in the Helio be due to a desire to keep
> them "original"?
>

No, Helio owners only care about STOL performance. The Helio requires high
power for takeoff only. Actually what it requires is high static thrust and
it benefits from a large diameter prop so that thrust flows over more of the
slats/wing/flaps. The geared engine can use a larger diameter prop without
the tips going supersonic. Once airborn, the airplane is not going to go
very fast (135-140kts) with its large wing and large exposed wheels no
matter how much power is availible.

The 350hp TIO 540 tends to overheat in the Helio probably due to the
cowling/baffling design. There were only about seven Helios made with the
TIO540 and at least three seem to be on the market at any given time, a dead
giveaway that the airplane is a lemon..

The 400hp IO 720 adds a lot of weight both in terms of the engine itself and
the additional fuel it requires.

Both the H700 and H800 (350hp and 400hp) were also designed to accomodate
both nosewheel and tailwheel configurations and they are heavier as a
result.

I was surprised that this was the case since generally later airplanes are
improved over earlier ones with various bugs fixed. MU-2s underwent a
gradual transformation over the ~20 yr production run where they got more
power, more pressurization, more fuel capacity, better avionics ect. I went
to OSH last year specifically to find out why all the experienced Helio
pilots preferred the H295 (295hp) to the H700 (350hp) and H800 (400hp). The
explanations varied somewhat but everyone thought strongly that the earlier
ones were better.

The ultimate Helio is a early model with an Allison turbine engine. I know
of only one that exists. This give you a larger prop, much more power AND
lighter weight, although fuel consumption eats up some of the weight
savings.

Mike
MU-2

[Jim Burns]

Thanks Mike!
Great explaination of desired airflow vs. HP.
Several years ago our aerial applicators mounted gearboxes and longer props
to their round engined Air Tractors. Not only did they reduce the prop
speed and noise but they increased the airflow around the airplane
produceing a better spray pattern.

Jim


> No, Helio owners only care about STOL performance. The Helio requires
high
> power for takeoff only. Actually what it requires is high static thrust
and
> it benefits from a large diameter prop so that thrust flows over more of
the
> slats/wing/flaps. The geared engine can use a larger diameter prop
without
> the tips going supersonic. Once airborn, the airplane is not going to go
> very fast (135-140kts) with its large wing and large exposed wheels no
> matter how much power is availible.
>

[Mike Rapoport]

I really want that 450hp Allison(!!!) but it would be at least a $250K
upgrade and I have a 80hr engine now. Supposedly it well take off in about
80' with the Allison..

Mike
MU-2


"Jim Burns" > wrote in message
...
> Thanks Mike!
> Great explaination of desired airflow vs. HP.
> Several years ago our aerial applicators mounted gearboxes and longer
> props
> to their round engined Air Tractors. Not only did they reduce the prop
> speed and noise but they increased the airflow around the airplane
> produceing a better spray pattern.
>
> Jim
>
>
>> No, Helio owners only care about STOL performance. The Helio requires
> high
>> power for takeoff only. Actually what it requires is high static thrust
> and
>> it benefits from a large diameter prop so that thrust flows over more of
> the
>> slats/wing/flaps. The geared engine can use a larger diameter prop
> without
>> the tips going supersonic. Once airborn, the airplane is not going to go
>> very fast (135-140kts) with its large wing and large exposed wheels no
>> matter how much power is availible.
>>
>
>

[Ron Natalie]

Jim Burns wrote:
> Mike,
>
> Just a few questions and thoughts, mainly because I'm curious.
>
> I'd be interested to know the HP rating of the GO480 installed in the Helio.
> I've been watching a few people that are building Bearhawks and one article
> mentions that the GO480 isn't favored for that application for the relative
> high weight to HP ratio compared to the 540.
>
The QueenAir uses supercharged 480's. The unblown engines run about 295HP
I believe.

There's no free lunch. While the gohpers get more HP out of less cubic
inches, the weight doesn't really go down because of the weight of the
gear box. The CG does go forward a bit though.

[Ron Natalie]

Mike Rapoport wrote:
> I really want that 450hp Allison(!!!) but it would be at least a $250K
> upgrade and I have a 80hr engine now. Supposedly it well take off in about
> 80' with the Allison..
>
Are you going to put the All-Terrain tires and the air horns on it too?

[Mike Rapoport]

"Ron Natalie" > wrote in message
...
> Mike Rapoport wrote:
>> I really want that 450hp Allison(!!!) but it would be at least a $250K
>> upgrade and I have a 80hr engine now. Supposedly it well take off in
>> about 80' with the Allison..
>>
> Are you going to put the All-Terrain tires and the air horns on it too?

No, I thought that thing was pretty stupid. The performance was about the
same as a stock Helio after they added 1000lb to the empty weight.

Mike
MU-2

[Jay Honeck]

>> Are you going to put the All-Terrain tires and the air horns on it too?
>
> No, I thought that thing was pretty stupid. The performance was about
> the same as a stock Helio after they added 1000lb to the empty weight.

Yeah, but it was soooo cool!

;-)

First train I've ever heard going over at 1000 AGL...
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

[Nathan Young]

On Wed, 22 Jun 2005 21:04:19 GMT, "Mike Rapoport"
> wrote:

>The ultimate Helio is a early model with an Allison turbine engine. I know
>of only one that exists. This give you a larger prop, much more power AND
>lighter weight, although fuel consumption eats up some of the weight
>savings.

I seem to recall a Sport Aviation article about a Helio or similar
STOL plane converted to turbine. The owners put a lot of crazy
conversions onto the plane. For example, they had a train whistle
driven by bleed air from the engine, a sprayer/fogger system for
killing mosquitos in the area prior to landing, and tires that looked
to be from a 4x4 truck.

One hell of a back country airplane.

-Nathan

[Darrel Toepfer]

Nathan Young wrote:

> I seem to recall a Sport Aviation article about a Helio or similar
> STOL plane converted to turbine. The owners put a lot of crazy
> conversions onto the plane. For example, they had a train whistle
> driven by bleed air from the engine, a sprayer/fogger system for
> killing mosquitos in the area prior to landing, and tires that looked
> to be from a 4x4 truck.
>
> One hell of a back country airplane.

Last I read, they were removing most of that, except the turbine that
is... To get better cruise performance... Guess it was fun for awhile
and then became impractical for frequent usage...