4-Place Bearhawk - Speed Mods?

[Oliver]

We eventually want to build an a high wing experimental aircraft to replace our Mooney with. While we technically don’t need 4 seats, we like to haul folding bikes and camping gear what pretty much mandates a 4-seater.

That being said, a Quick Build 4-place Bearhawk would appear perfect – if it only were faster.
We are willing to give up some speed compared to our Mooney’s cruise speed of 150kts @ 9.8 gal / hr @ 8,000 ft. Since we travel quite a bit, the cruise speed should however not be less than 135 kts @, let’s say, 12 gal. / hr.

Based on what I have seen so far, the Bearhawk seems to cruise at 110 – 125 kts, most pilots however appear to have bigger wheels installed.

Considering a desired cruise speed of 135 kts @ 12 gal. / hr, I am wondering if am asking something the Bearhawk is not designed to do or if it is possible to achieve this cruise speed with relatively simple modifications like wheel pants, fairings, etc?

Btw.: The Bearhawk website suggests a cruise speed of 150 mph (130 kts) @ 62% power with the 260 hp engine. I could probably also live with that, if it was indeed realistic.

Oliver

[Mark Goldberg]

Hello Oliver. The new Model B Bearhawk is faster than the 130 kts at 62%. I think your 135 kts is doable with a 540 engine and good c/s prop. On its way back from Oshkosh last year - at 6,000 - 7,000 ft my 540 powered BH had a TAS of around 157-158 mph burning around 12 GPH or a little less. To get that speed you have to be in the sweet spot of those altitudes where most planes get their best TAS. Mark

[Battson]

Especially true airspeed. We were disappointed if we didn't see 130 KTAS above 6,000ft at all times (this was before new wingtips, VGs, big tires).

If you used wheel pants, streamlined flying wires, and most importantly an efficient engine cooling design - then 135 KTAS should be easy with the new B model wing for less than 10 GPH. I would add fuel injection to help with both speed and fuel economy.

[Oliver]

Mark, Battson, thank you for your responses! This is awesome and actually matches the specs on the website, which I thought would be a bit optimistic.
The Bearhawk appears more and more to be the perfect do-it-all plane for us!

[Mark Goldberg]

Oliver - you will find mostly that the actual performance numbers usually are BETTER than the specs we put out. There are many airplane and kit manufacturers that shall we say "exaggerate" their numbers. We understate the performance specs. Mark.

[Rollie]

FWIW Before I ordered my Patrol kit I flew my Pacer down to Bob Barrows strip to check out the Patrol prototype and to see how exaggerated the performance numbers were. At the time they were advertising a 140 mph cruise speed in the Patrol. We went for a little demo flight and that thing took off and climbed like crazy and while leveling off on downwind went right through 140. It didn't take long to realize that the numbers Bearhawk shows on the website are conservative, not exaggerated. I ordered the kit a few weeks later and have been flying my plane since late this past winter. I didn't do anything that will make the plane fast, I wanted a good STOL plane that was faster than a supercub. I love my Patrol. It will get in and out of anywhere I want to go and at 6000-8000 it trues out a little over 130 kts at gross.

[Oliver]

This all sounds great! Thank you very much again for your responses, I really appreciate it.

[fairchild]

How about a nice set of graphite wheel pants ? Would that give 5 kts?

[Isilverone]

Will find out soon what 200hp and wheel panties do,, lol

[Battson]

Will find out soon what 200hp and wheel panties do,, lol

That paint job though! Wow!

[rv8bldr]

Will find out soon what 200hp and wheel panties do,, lol

As Jono said, WOW! Nice paint!

A couple of questions about your wheel pants: are they home brew or did you buy them? What size tires are underneath? I sure would like a few extra knots on my 4pl when it is done. I recently sold my RV-8 which cruised at about 160kts and bought a Maule which cruises at 110kts (ugh!! Sure made for a slow trip home from Lethbridge to Ottawa) I would like to squeeze as many knots out of my 4pl as I reasonably can. I fly off of a home grass strip, and that is probably as "backcountry" as I will get, so those wheel pants of yours would be perfect.

Cheers

[JimParker256]

In the "for what it's worth" department... I put the wheel pants on my Citabria (O-200 powered 7ECA with 7:00x6 tires) and my cruise speed went from 90 mph to (drum roll...) 92 mph. Taking them back off now, as I'd rather have the extra UL for fuel (20 lbs = 3+gal).

[robcaldwell]

That paint job though! Wow!

I got to see Mike's Patrol build in person at his place in Saskatchewan a few months ago. Mike is a talented builder and loves to paint! This bird will really stand out next year at OSH!

[schu]

Wheel panties.... hahahaha

I have 31" tires on order for mine. Obviously speed is secondary to my mission.....

[PaulSA]

One thing to consider is that any wheel pants are likely to take a hammering if you plan any rough field work. If you are going to build them, build them strong. I have had several repairs and reinforcements to my RV-10 and I only operate out of a relatively smooth grass strip.

[svyolo]

I am not sure I would call anything done to a BH a speed mod. I think efficiency mod might be better. Ultimately you are pushing a large, thick, high lift wing through the air. That is going to stop you from accelerating eventually, no matter how much power and fuel you throw at the problem. I would be trying to go a reasonable speed, for the least amount of fuel.

I haven't paid attention to anything like a BH, well, ever. I went to the airshow in Arlington WA in July. I saw a couple of beautiful Patrols, and a few Maules, Pipers, etc. I was amazed how much cleaner the Patrols were than anything else in the category, or speed range. A lot of speed mods are built in to the design. The basic airframe is much cleaner than anything other than maybe a Glastar.

If you are bucking headwinds, speed definitely helps. Wheel pants help a lot on an RV or Glasair at their cruising speed. On a BH, they will help a lot less. If they fit your requirements, by all means put em on, along with every other fairing you can.

For me, light is more important than slick. I wish I could have both but big wheels or floats are going to mask any attempt at slick for me.

[Isilverone]

Hi guys, as stated above,these panties are an efficiency mod. I really like the looks of them more than anything. If I can cruise nicely along with an inch or 2 less MP , then they’ve done the job. I’ve always had big fat tires on my planes and just wanted to try something different. I’m hoping the wings and tail stay cleaner also. I’ve got a streamlined tail spring fairing and a very streamlined fairing system over my landing gear struts so should look fast if nothing else. The panties came from RF-Ski in Germany. They are for 8.50 tires and are actually built for the Aviation Husky. I’m really impressed with the construction and finish.. I’m very close to getting this thing finished and looking forward to first flight..