EXCLUSIVE: Compass 7HV Close Up – Photos

I had the opportunity to meet with Team Compass at the Birmingham 2011 Fun Fly. They were kind enough to allow me to photograph 7HV and we discussed some of the details of this fantastic helicopter. Click for photos and details.

I arrived in Birmingham around 8:00 a.m. Friday March 18th and made my way down to the Compass booth to meet with Tony Whiteside and David Kettelhut. I wanted to get my hands on the Compass 7HV so I could get a feel for what it is really like. The 7HV is still at prototype status and going through heavy testing with the Compass Team Pilots. We have already covered some of the test videos along with footage of flights from Rotor-Live 2011. We also covered 3D CAD rendered images showing some details of this helicopter. The 7HV is an impressive piece of work so far. Tony Whiteside allowed me to photograph the heli and said “Go ahead, pick her up… set her in the grass and shoot some pics.”. I thanked him and proceeded to studying the heli as close as I could. Carrying it from the table to the grass I immediately noticed how light this helicopter was with no batteries in it. As I started photographing the 7HV a crowd gathered around to get a peek at it.

The configuration I saw was sporting a HobbyWing 120 Amp HV ESC, a 2S receiver pack, a BeastX microBeast 3-axis flybarless Gyro, EDGE Flybarless main blades, KBDD tail blades, JR 8717 cyclic servos, an Outrage TORQ tail servo and the stock Compass brushless motor. The motor appeared to be around the same diameter as the 540KV motor in the 6HV, but it was taller. The motor in the photos below is sitting upside down in the helicopter awaiting installation. I was told the stock Compass motor makes plenty of power for the 7HV. The ESC sits on a carbon fiber (CF) plate toward the font of the helicopter. The width of the 7HV frame allows for generous amounts of space for mounting of electronics as well as a large battery compartment. There are some unique features to this helicopter such as a tensioned guide pulley system that will use springs or a rubber band type of mechanism to control belt tension automatically. The all-metal tail case is similar to the construction seen on the 6HV, but it has idler bearings over and under the tail pulley to prevent belt slippage. Overall the tail is similar to the 6HV but beefier. The tail has more aluminum components than the 6HV and is the tail control lever is over slung instead of under the tail box. The steel modulus 1 – 13 tooth pinion is supported with a counter bearing, attached to the motor mount which should hold up to any vigorous 3D flight. The motor is mounted over the main gear raising the CG of the bird.

A typical feature of the Compass Model lineup is a component layout optimized for a high Center of Gravity. This contributes to smooth as well as fast cyclic maneuvers. High Center of Gravity (CG) also compliments a flybarless setup nicely. The servo cage is CNC aluminum and aligns the servos under the swashplate for direct-drive performance. All servos are mounted over the tail boom axis, thereby assisting the higher CG of the machine. The servo cage also holds 2 of the 3 main shaft bearings. The heavy duty elevator swash guide is mounted atop the CNC aluminum servo cage. All frame supports and spacers I could see were CNC aluminum for strength and bling factor.

The head and swashplate are very similar in design to the Compass 50-sized flybarless head. The Rotor Hub and Grips are beefed up for the rigors of 3D with a 90-size machine. The tail boom supports run to a single mount point on the underside of the tail boom support which is made of what looks like a heavy duty plastic. The carbon tail control pushrod runs through a guide on the top of the tail boom support. The tail boom support is the single guide for the top-mounted tail control pushrod. The tail boom looks strong and large in diameter adding to the tough overall look of the helicopter.

The side frames are a stacked, 2 piece design. The lower portion of the frames that house the batteries are made of thick carbon fiber and are replaceable separate from the upper frames to cut down on rebuild time and cost in a crash. The batteries mount to a carbon fiber plate under the mainshaft where the CF plate protects the batteries from the mainshaft in a crash. It also provides a high mount point near the tail boom axis for the batteries in the generous sized battery compartment. There is also a CF plate that runs between the skids mounted to CNC aluminum spacers that the landing gear mounts on. This bottom plate most likely aids as a frame stiffener as well as adding protection for the batteries in the event of a crash. The tail boom supports mount to the CNC aluminum frame spacer toward the rear of the helicopter that is bolted to the bottom CF plate and the landing gear. This should all solidify the beefy, wide frames. The upper frames are held together with CNC aluminum frame spacers toward the front of the bird, the CNC aluminum servo cage over the main gear, and heavy duty CNC aluminum tail boom blocks in the rear of the heli. The layout of the frames and servo cage appear to offer easy access to all components of the helicopter for maintenance and repair. All parts had a nice finish to them even though this was a prototype.

Specifications:

Length: 1372mm
Height: 403mm
Rotor diameter: 1560mm
Pinion: 13T
Gear ratio: 13T: 10.46:1:4.8
Flying Weight: approx 4.3 – 5.1kg
Motor Type: Brushless Outrunner
Battery Size: LiPo with 12S (2 x 6S) 4000-6000mAh
Blades: 690-710mm

Release Date:

When I asked Tony Whiteside about a release date he replied “When it is ready”. Based on my discussion with Team Compass they intend to test the 7HV exhaustively to work out any bugs before a release date is considered. When the 7HV is ready, I’m sure there will be plenty of Compass fans that will also be ready for the production model release.

Special thanks goes to Team Compass for discussing details of the 7HV and allowing me to photograph the prototype.

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