Parson's Trainer

cbonnerup

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Group,
My copy of the LTP300 plans place the HS trailing edge very close to the prop. Any comments on the performance? Seems to be not much of an 'arm'.
Thanks.
 

Mike484

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Do you have a copy of these plans electronically that I may be able to acquire?
 

cbonnerup

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plans

plans

Do you have a copy of these plans electronically that I may be able to acquire?
Certainly,
I just need an address that will accept a 3.1MB pdf. It's full res/size at ~ 40 pgs.
Please let me know via PM. Be happy to oblige.
I believe they're public domain now; drawn in 1990.

Good Day,
Chris
 

Mike484

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Sent PM. I have some Parson's plans, want to compare and see if yours are different from mine.
 

Mike484

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I agree with the tall tail and since they are still readily available from Ernie, it is a very good choice.
 

Aussie_Paul

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cbonnerup

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Correct,
They ain't the same.
I would really like to see constructive anecdotes or numbers on different style tail feathers.
Not convinced of the effectiveness of the steerable HS on the 'tall tail' designs.
Especially if it has +/- lift.

Dazed and Confused it seems,
Chris
 

C. Beaty

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A tall tail on a Parson’s trainer will improve handling in every respect.

Those individuals who don’t think so are extrapolating the bad experience they’ve had from using a tall tail on an RAF or SparrowHawk, shedding alternating vortex sheets.

A Parson’s trainer doesn’t have a chopped off cabin back.
 

Chris Burgess

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I'm with Steve here. I flew the Parson's tandem (first generation) for 10 years, Mac engine, no prerotator, no horizontal just twin expansion chamber mufflers. Well somewhere in there I had a crankshaft failure and the prop flew off into the rudder taking off the top counter-weight section at the rivet line and shearing the top hinge pin of three that it had. Handled fine all the way to the ground. CG shifted forward a little but nothing else there. The Skywheel rotor struck the prop as it flew off.

Let me tell you, if that had been a "tall tail", it would have gotten VERY UGLY very quick.!!! Give me the solid metal tail with only part moving rudder anytime. Hey Steve.!!!

Yes a tall-tail improves some issues but if that top pivot gives way, good luck. The Parson's still is the best trainer for those who will fly a similar open frame short tail aircraft.
 

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KiwiBird

ATO Gyro Instructor, NZ
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Hello Chris,
Do you have any Pilot Manuals or maintenance manuals for the Parsons Trainer? I have a student who has purchased one and we are lacking any details on flight envelope etc.
Thank you in advance

Regards
Trevor
Twizel
New Zealand
 

Chris Burgess

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Hey Trevor,
I had what I guess qualified as a flight manual but it was pretty much written by me and approved for use at the time by the PRA tech committee 1989. I don't have any of that stuff anymore but using a Bensen B8M flight guide would be nearly the same. All the flight numbers need to be established for each aircraft as no two are alike. I flew many models and each one was unique. I think it would be wise for someone experienced (CFI type) to establish those numbers and write a guide. Just curious, is it a Parsons II "short" or the extended Parsons II. They are quite different.
 

C. Beaty

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I was flying down the runway, several hundred yards behind Steve McGowan in his Parsons Trainer at a Bensen Days at least 20 years ago when he did a hammerhead and ended up headed straight for me. I immediately dove for the runway and landed, deciding the sky wasn’t big enough for the two of us.

Only later did I learn that it wasn’t entirely Steve’s fault; his overloaded, tailheavy Skywheels rotor would suddenly and unpredictably become divergent and stand the machine on its tail. Steve, in order to mask what had really happened, would do a hammerhead to make it look like a planned maneuver.

One of his students later told me that the abrupt tail stand was a common occurrence and Steve would yell; “I’ve got it.” The degree of instability of Skywheels is a function of blade loading; with lightweight gyros and low blade loading, instability resulting from tail heaviness is fairly mild and often misinterpreted as “High Lift” or “High Inertia.”
 

KiwiBird

ATO Gyro Instructor, NZ
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Hey Trevor,
I had what I guess qualified as a flight manual but it was pretty much written by me and approved for use at the time by the PRA tech committee 1989. I don't have any of that stuff anymore but using a Bensen B8M flight guide would be nearly the same. All the flight numbers need to be established for each aircraft as no two are alike. I flew many models and each one was unique. I think it would be wise for someone experienced (CFI type) to establish those numbers and write a guide. Just curious, is it a Parsons II "short" or the extended Parsons II. They are quite different.
Hello Chris
Gee, I am not sure if its a short or a long, but it is two seat with a tall tail. I am what you call a CFI Instructor in Gyros and Fixed wing Microlights, which all Gyro's are here in NZ.
Regards
Trevor
 

okikuma

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Hello Chris,

I just wanted to restart this thread with a couple of questions about the Parsons ll design.

Over the years, I have noticed in various photos of "Parsons Tandems" with different spacing between the fore and aft rotor masts.

Did Bill Parsons design two versions, or the difference in keel length is because of various copies of his design?

In looking at your photo of the departed prop from your "first generation" Parsons tandem, it appears that the two cluster plates that attach the fore and aft masts to the keel are nearly the same distance as the Brock style rear seat/tank, leading me to surmise that your Parsons was of the "short" type.

How effective was your Parsons for training compared to your SnoBird tandem?

What was the empty weight of your Parsons?

Thanks,

Wayne
 

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Chris Burgess

GYRO-CFI
Joined
Oct 30, 2004
Messages
780
Location
Winter Garden FL 34787
Aircraft
Many makes and models, prefer open frame, Sold my SnoBird Tandem
Total Flight Time
3400+
Hello Chris,

I just wanted to restart this thread with a couple of questions about the Parsons ll design.

Over the years, I have noticed in various photos of "Parsons Tandems" with different spacing between the fore and aft rotor masts.

Did Bill Parsons design two versions, or the difference in keel length is because of various copies of his design?

In looking at your photo of the departed prop from your "first generation" Parsons tandem, it appears that the two cluster plates that attach the fore and aft masts to the keel are nearly the same distance as the Brock style rear seat/tank, leading me to surmise that your Parsons was of the "short" type.

How effective was your Parsons for training compared to your SnoBird tandem?

What was the empty weight of your Parsons?

Thanks,

Wayne
Yes there were two versions. We had the first generation, shorter in length and height, I believe also in width. I really enjoyed that shorter version. It was in my opinion one of the best for the open-frame single seat students at the time. It was more stable in pitch than the SnoBird, at least I felt that way. The one photo you have showing the "original" version hanging from the ceiling (is that in the museum at West Chester PA?) N54WP, that is what I had. The very basic trainer, no pre-rotator, no electric start, no in flight adjustable trim. Used it for 10 years. It had some issues like the rotor could strike the prop if you allowed it to excess flap on the ground. Like several of today's gyros, they count on your prerotation and proper technique to keep you out of trouble in that area. I'm a believer in not letting the rotor and prop planes intercept one another statically.

I had to do the prerotation for the student while he/she held the stick forward. Then I "straddled" that seat and yes, it was a bit "tight". The stick was another problem area as it shot off to one side 90 degrees and then was curved up to your hand. So you flew with your hand way out there is "space" to your right. It became second nature to me of course. But that 90 degree offset became a high stress area which was prone to cracking. I think I replaced it about three times in those 10 years from the appearance of cracks. I believe the empty weight of the Parson's was 390 pounds. The SnoBird was 587 pounds. The Parson's "short" had the super MAC at perhaps 90 hp on a good day, while the Snobird had 100 hp in it's initial configuration or 115 hp with the Mikuni carbs. The poor Parsons was at full throttle most of the time with all the heavy students. So that engine was not a "happy camper". I always felt it would blow at anytime and that is how we flew it. "Never fly over anything you can't land on or glide past" I say. Having barely enough power to make traffic pattern altitude made you a better pilot for sure. The Parsons rotor was 25 feet and we went to 27. I started with 28 on the SnoBird, then 29, and ended up at 30. 29 may have been better as the rotor would have turned a little faster. I like a faster turning rotor.
 
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