Sopwith Baby Project

[DamianL]

Hi Joe

Just curious, how did the relatively light & small airframe of the Sopwith Baby handle during take-off with the high gyroscopic effect of the rotary power plant?

The handling difficulties of the Camel are well documented, but I'd imagine these effects may be magnified & more difficult to control in a floatplane.

Have you come across any period documentation which describes the handling characteristics or the Baby or Schneider?

Damian

[Joe Perkel]

Originally Posted by DamianL

Hi Joe

Just curious, how did the relatively light & small airframe of the Sopwith Baby handle during take-off with the high gyroscopic effect of the rotary power plant?

The handling difficulties of the Camel are well documented, but I'd imagine these effects may be magnified & more difficult to control in a float plane.

Have you come across any period documentation which describes the handling characteristics or the Baby or Schneider?

Damian

Damian,

You bring up a good point regarding handling, however I was always under the impression the main issue in flight characteristics would have been the drag and not so much the gyroscopic effect. The float assemblies themselves at 65 lbs ea, would provide both a lowered cg pendulum effect, and aerodynamic stability against the twisting moment of the engine mass. The problem they had, (maintenance issues aside), was an occasional engine out approach and landing.

Even with the engine running fine, there is a reference in the text "Ben My Chree, Isle of Mann Packet Steamer and Seaplane Carrier", Burns 2008. "The single seat Sopwiths had a reputation of being a "hot ship" and difficult to land."

Logistics aside for a moment, this issue of not being able to adequately match the original thrust requirements with modern power within the design constraints of the airframe, is a major factor in my decision process.

[David Paule]

Regarding the Strutter, I believe that the pilot sat in the front cockpit. It might make sense to move the pilot to the rear seat for better visibility and less center of gravity variation when carrying passengers.

Also, without the weight of the guns and ammo, the short nose pretty much demands a heavy engine. I'd think that without that, you'd have difficulty getting the center of gravity to a reasonable location.

Once that is under control, the Strutter appears to have a longer distance, a longer moment arm, between the center of gravity and the tail than some of the other WW I airplanes. This is good. There might even be enough tail volume. Tail volume, this moment arm times the tail area, is a fundamental factor in obtaining good stability, and by modern standards is sometimes lacking in WW I airplanes.

The gyroscopic precession is basically a function of the rotating inertia of the engine compared to the mass moment of inertia of the rest of the aircraft. Obviously the control power of the ailerons, rudder and elevator plays a part in it, but the inertias I mentioned are probably the main things. If you install a rotary, well, you'll need to learn to fly it. If not, there's no problem there. But even with one, the relatively large size of the Strutter means that the engine precession will appear of less significance than with the smaller airplanes, simply because inertia goes up as the square of the aircraft's size, and linearly with its mass or weight.

Finally, as to power and thrust, that's been discussed here before. I'd simply like to repeat a comment a friend made once. "Too much is almost enough, " he said.

[Joe Perkel]

It's been a fruitful learning experience, but with the decision to switch to a land based replica, this dedicated thread no longer serves it's intended purpose.

With that then, I shall continue forum participation, but no longer maintain this thread. I will start a new thread for the Sopwith 1 1/2 Strutter when I actually begin construction upon the nearing completion of my house and shop. It is also my intention to reconfigure the web-site, and continue CAD work on the Baby concurrent with component construction for the Strutter.

I wish to thank all who participated and contributed to what has turned out to be an extensive preliminary education for the impending real deal!

With Warmest Regards

Sopwith Baby virtual pilot, ....over and out.

[Joe Perkel]

I have updated my web site with some images of the tail float structure for the Baby / Schneider. Very interesting carpentry detail involved in these float structures. The recent LE cutting discussion on the Nieuport thread has peaked my interest. Many thanks to Bob, for his recent help in my router table education.

Will be starting one of two Sopwiths in relatively short order after a nearly two year run up, and I must say that I have received literally global pressure on continuing with the Sea Plane.

Let me also say that inspiration can come from the simplest of off hand remarks. Maxim08's mention of his yellow and white RV-7 at Sun -n- Fun, causes me to question the value of passenger carrying capability in a WWI replica. After all, one can always rent a seat for a passenger who might not distinguish one airplane from another.

My never ending gratitude to those who have supported me in this incredibly long preparation to start up. To those who have grown weary of it, I can only say, "taxi into position and hold"!

[Joe Perkel]

"...What I have found is that if you are 'all hat and no cattle' people are polite and encouraging but don't go out of their way to help (especially if legal liability is involved). If you actually have a go and start into a project, you get an excellent response and a lot of help..."

Bryan,

So very very true! I liked that saying so much, that I had put it on my future photo log page, (take a look at what I replaced it with yesterday).

"A fool learns from his own mistakes, a wise man learns from the mistakes of others". I think this forum is a great way to share knowledge about the dangers of what we do."

You are just spilling with wisdom today!

Let me share with you all, a mistake that you can learn from at my expense. (This is off topic, but useful). This is about contract law, the reason my project is "Big Hat, no Cattle, and the old saying, that "Possession, is nine tenths of the law".

A lesson learned, a lesson shared. (Off Topic)

My home addition is large, total contract value nearly 300k, in 6 installments at various stages of construction. By the third installment, I knew the contractor was in financial trouble based on activity, and other warnings.

Just prior to the 3rd installment, I contacted my lawyer as to my liability to pay that third payment in full. I wanted to break the terms and pay it out piecemeal at that point. The lawyer said that the contract precluded me from doing that, and that I was liable for the payment in full.

Mind you now, these construction contracts are heavily loaded in the contractors favor so that they can (in theory) work off of your money for the next stage. In theory. After that payment (60K), my contractor said, "Sorry Charlie, I'm out of money, spent it elsewhere".....Oops! What do you do now? Sue the guy, and collect what? So I reached an agreement where he has "worked off" the misappropriation and we are now finally, after 1.5 years, nearing completion.

I'm not here to make friends, so why tell you all this?

Because I consider this forum to be a useful tool to complete an objective. I owe an explanation to those who have been willing and able to contribute now and in the future, that I am not just blowing smoke. After going through this hell while concurrently planning this build, I don't think I've done so badly.

If I have wavered a bit, you now can see clearly why that has been. Desire, ability and opportunity are finally coming together shortly. Only the unforeseen can stop me now.

[brinesharks]

Hi Joe,

I hope you don't think I was aiming my comments at you - I think the 'big hat, no cattle' applies to me!

Your contributions on this forum and your web page are very valuable. Even if you never build a plane, your work using CAD to model the airframe of a rare prototype has inspired and educated many.

Plus - your webpage really sets the standard for project sites!

[Joe Perkel]

Originally Posted by brinesharks

Hi Joe,

I hope you don't think I was aiming my comments at you - I think the 'big hat, no cattle' applies to me!

Your contributions on this forum and your web page are very valuable. Even if you never build a plane, your work using CAD to model the airframe of a rare prototype has inspired and educated many.

Plus - your webpage really sets the standard for project sites!

Thanks Bryan,

More like "aiming them at myself". The frustration level that I am experiencing is acute. I have a plan, (a good one), the means and the ability to implement it, but opportunity continues to elude me through no fault of my own. It's like having a glass of water just out of reach when dying of thirst.

It's been over a decade of deciding what project to actually implement, and nearly two years now of having made the choice.

Just a little venting but, I really should know better. I know what real problems look like, I see them at work every day. In reality, I have no problems!

[hank jarrett]

The guys with cattle are the luckiest ones, but there are two types of "big hat" people. Those with empty heads inside and those with full heads (OK there are two types of full heads too but we won't go in to the heads full of "you know what" in detail). This site seems to have a large number of big hat people with really valuable information in the heads wearing those hats. The other nice thing is the heads full of "you know what" seem to expose themselves pretty quick. None of us should be upset by the big hats with empty heads. It's our jobs to fill those heads with the right information. That is out cattle breeding program. We all are together in wanting our own cattle.
Hank
We have to get back to head filling. This message gave me a headache.

[drrivah]

Joe-
Saw these at NASM Udvar Hazy this weekend. Not Sopwith, but are period construction (Curtiss NC10B)-may be of interest. NASM left the right side unfinished.

-pete