Gross weight between patrol and bearhawk

[Zook]

So I’m comparing the 4 place and the patrol. Why is there a weight difference between them ? As far as I can tell the wing and tail are the same size between them. The only thing I can see is the 4 place is a little longer then the patrol. Is there something I am missing ? I bought a set of building Manuel’s from Eric last week and looking forward to reading them. Will order a set of plans in the next month.

[Bcone1381]

I will take a guess. I believe Bob Barrows engineered the wing and gear in accordance with his design goals...meaning he wanted the Patrol to be as light as it could be, and run out of space before hitting Max Gross Weight if two 200 pound people went camping with full fuel.

So, the Cap Strip thickness, length, and maybe material, used in the Patrol will accommodate 2000 pounds under the Utility Category, while the Model B accommodates 2500 pounds.

The wings of the Modle B and Patrol are not the same.

[Chris In Milwaukee]

I concur with Brooks. Patrol and BH4B wings share the same airfoil (and perhaps span) and some parts, but the spar has some differences.

[Zook]

I don’t have plans here to look at. Just going by the sqf of wings.

[rodsmith]

Narrower fuselage and lighter tubing in places saves some pounds.

[Zook]

What is the baggage area weight capacity between the two. I can’t find that. I prefer to build a patrol but if the baggage area can’t carry much weight then I would go with the 4 place and just install two seats. Most of my trips will be just me and one other person on day fishing trips with the occasional trip.

[Mark Goldberg]

Zook - every plane is different in this experimental world. In the 4 place it matters quite a lot if you have a 540 and C/S prop up front. That weight allows you to better use all that space in the back. LOTS of room in the 4 place, but you can run out of CG.

In the Patrol - it also depends. If you do not have a 250 lb guy in the back seat no reason you can not haul 100 lbs + plus in the baggage area.

My suggestion would be to do some calculations yourself using the weight and balance info on Bob's two prototypes keeping in mind that his planes are always the lightest. There is no real weight limitation. It is the CG that limits loading aft. Mark

[Chewie]

My suggestion would be to do some calculations yourself using the weight and balance info on Bob's two prototypes keeping in mind that his planes are always the lightest.

I'll do just that Mark. Where can I find this info?

[Mark Goldberg]

Bob's Patrol W & B was in a BearTracks. So are both his prototype Bearhawks. That is where to find Bob's info. But you should get it from other builders since Bob's planes are so light. Mark

[Bdflies]

Not sure about Bob's, but Eric's numbers are here;

https://bearhawkforums.com/filedata/fetch?id=1546

Note: Eric built pretty light!

Mr Zook, I won’t state any numbers beyond the official weights listed for the Patrol, but I can state (with some authority) that the plane flies very well even when loaded with too much stuff. My time in a 4 place was too long ago and was lightly loaded, so I can’t make claims or observations of capabilities. The Patrol, however, is a roomy, comfortable, load carrier that’s probably faster than everything else in its class.
If you and a buddy want to do a fly out camping trip, for a few days, and can’t carry your stuff in a Patrol - you’re packing too much stuff!

Bill

[Chewie]

Thanks Bill.
I notice Eric assigned his front seat at an arm that's forward of the empty CG. So a pilot shifts the CG forward? I assumed virtually any load in the patrol would shift it back. I need to eat more donuts!

[Bdflies]

I guess I never really thought of it that way. My empty CG came out to 14.45". I have full aluminum panels, tundra tailwheel (HEAVY), heavy upholstery and a light prop. There's about 4" of seat travel available, so it's kind of a good approximation for pilot seat arm. But, yeah, my 'most forward CG' is ahead of the empty plane.
I wouldn't recommend donuts, though. I'm living proof of the folly in that theory.....

[kilohotel]

I assume most folks have already seen the following video on YouTube, but just in case....this should pretty much answer any questions about the baggage capacity in the 4-place...

https://www.youtube.com/watch?v=6rgnbjviNhg

[Zook]

As far as I can find the patrol will do what I want it to if I install a belly pod. Anybody try this. I use to fly a 185 with a belly pod and it made it easy to keep it in cg. Didn’t really notice any handling difference. Cooling was an issue some days. This was in the mountains of Guatemala. I never flew it with out the pod so can’t say what it cost in mph. The real reason I want a patrol is the center line seating. Other then that the 4 and the two seat perform the same as far as I can tell.

[whee]

As far as I can find the patrol will do what I want it to if I install a belly pod. Anybody try this. I use to fly a 185 with a belly pod and it made it easy to keep it in cg. Didn’t really notice any handling difference. Cooling was an issue some days. This was in the mountains of Guatemala. I never flew it with out the pod so can’t say what it cost in mph. The real reason I want a patrol is the center line seating. Other then that the 4 and the two seat perform the same as far as I can tell.

Because of the main landing gear configuration a belly pod will do little to help with CG. The shock struts attach to the air frame further aft than those on say a Supercub which pushes the belly pod aft thus eliminating much of the CG benefit found on most pod installations. The pod on your C185 was very far forward and those airplanes have a large CG range so you can't really draw any comparisons.

All that said, I will be installing a pod on my 4-place because I need the cubic inches and will benefit from the minor CG loading advantage.

[Battson]

Because of the main landing gear configuration a belly pod will do little to help with CG. The shock struts attach to the air frame further aft than those on say a Supercub which pushes the belly pod aft thus eliminating much of the CG benefit found on most pod installations. The pod on your C185 was very far forward and those airplanes have a large CG range so you can't really draw any comparisons.

All that said, I will be installing a pod on my 4-place because I need the cubic inches and will benefit from the minor CG loading advantage.

I dare you to put the pod on the roof... Take the "Bearhawk hump" to a whole new level!

[svyolo]

You gotta love thinking outside the box. How about wingtip pods? I still think a 12 gallon "aux" tank in the aft fuselage/tail might make a good performance mod for a STOL comp. If I remember right P-51's had a big "aux" tank behind the cockpit. They burned it before they got to the point of combat because the aft CG caused controllability limitations.

[whee]

I dare you to put the pod on the roof... Take the "Bearhawk hump" to a whole new level!

Haha! But wait...that might work.🤔

[Rollie]

I set the max gross for my Patrol at 2100 lb. I can and have flown it with full fuel, two people and 140 lbs in the baggage area. That put me at 2093 lb takeoff weight and 20.37 cg. Very close to weight and aft cg limits. The plane flies fine like that. Honestly the only difference I noticed between that and solo was the position of the trim lever. I suppose it took a few more feet of runway but nothing significant.

[Bdflies]

I’m not going to state my number, in compliance with Jared’s wishes. But my experience mimics Rollie's. The Patrol just doesn’t care. Takeoff roll is a bit longer, but it flies about the same. Honestly, probably the most CG forgiving plane I’ve ever flown.

Bill

[Battson]

The four place is the same in some ways. I cannot exactly measure the aft CG, but I suspect I have been more than close to the limit. Weight is harder in the 4 place, I put mine at 2,700 T/O max weight and I haven't been able to get that heavy. I would need to start over-eating.

But in other ways, its different to the Patrol as reported. When flying near the weight limits, the takeoff performance degrades remarkably at 2,600lbs compared to 2,100lbs. Every horsepower counts.