View Full Version : Info on Rocket II and III

04-01-2009, 08:21 AM
What are the differences between the Rocket II and III?

Are they both based on the -4?

Sorry for the simplistic questions but the Rocket site is pretty scrambled.

04-01-2009, 10:45 AM
Go to http://www.harmonrocket.com/ and click on SPECS, or HRII&III, and you'll get a table with HRII spces in black and HRIII specs in red. The main difference, of course, is that the HRII is two-seat, and the HRIII is single seat.

04-01-2009, 11:41 AM
HRII Fast....HRIII Faster..

Jeff Brenhaug
04-01-2009, 01:29 PM
Go to www.harmonrocket3.com and see the only flying HR3 thus far. Although a few of them are close to being airborne.

04-01-2009, 08:13 PM
Jim's not too far away with his HRIII at LVN. He picked up a bunch of electronic goodies this week, so it won't be too long until you'll have a flying partner here in Minnesota that can keep up with you!


Jeff Brenhaug
04-02-2009, 05:42 PM
Hey Stein,
Keep the pressure on Jim to git 'er done. I'm heading overseas for a few months and want to see some progress when I get back.
p.s. NO, you can't fly it while I'm gone.

04-03-2009, 07:04 AM
It is pretty scrambled.

The basic difference is:

HR2 is a two seater based on a widened RV-4 fuselage in the front seat. Back seat RV-4 size. This adds (help me here) about 6 inches width up front. I believe it still uses the RV-4 canopy. Wings are clipped vs. RV-4 and more ribs are added. Many skins are increased to 0.040 thickness.

HR3 is a single seater flown from what was formerly the rear seat. Still based on the RV-4, but NOT widened. Uses special canopy. Wings are clipped even more than HR2 and another rib is added. Skins same as HR2.

The higher speed is from the narrower fuselage and shorter span. Empendage is stock RV-4 with the 0.020 skins substituted for 0.016 like the later kits.

When I build mine, I'm thinking to build a HR4 -- 2 place, narrow body, flown from the rear with the higher performance engine. Seems the best of all worlds. I like the idea of a removable auxillary fuel tank, too, that will swap in for the front seat for extended high speed cruise. Have also toyed with idea of being able to switch back and forth between two place and single place canopies. What the heck ?

Hope I got all of that right. Feel free to correct anything that's wrong guys.

Final thought. It's definitely not a "kit". Harmon's "plans" are definitely not Van's level quality. You build this thing; not assemble it.

04-03-2009, 10:07 AM

All that sounds good except that HRII front 'pit is only 4" wider than RV-4. Because of that, the canopy is wider, too.

04-12-2009, 03:28 PM
If anyone is seriously considering building a Harmon Rocket III, I have a set of plans for sale in the VAF Classifieds:


$100 shipped to US address

04-26-2009, 05:22 PM

The HR2 by far is the best cockpit setup of any of the RV's I have flown. It is 4" wider at the shoulders than the RV4, which is alot. However comma, it is much wider at the panel and has much more "total" room up front than the 4 or the 8. Having spent 5 years building and 10 years flying a -4, the HR2 cockpit is vast (very similar in size to the F-16) and has much better visibility than the 4.
All of the previous posts are accurate, but they don't stress how fun, fast and efficient the HR2 is compared to ANY airplane, much less an RV. This week I flew alongside many of my RV SNF visitor friends and forgot how amazing the HR2 is...

Simply put, it Rocks!


Jeff Brenhaug
04-26-2009, 05:32 PM
Couldn't agree with you more.
Everytime I fly the HR3, I fall in love with it all over again and can't stop smiling for days afterward.