Recently, I have lost a plane, and now I have rebuilt a new one. But now I have run into range issues (using V2 Dragonlink). The previous plane was a Hobbyking Sky eye, with Rx antenna glued to leading edge of the tail (foam) and had excellent range (never a failsafe before 20 km in low power, and quite flyable up to 40 - 45 km with occasional failsafe).

The new plane has quite similar electronics, but I built it from scratch: the fuse is fiberglass, the vertical and horizontal stabilizers are balsa covered with monokote, and the wings are modified from Diamond 2500.

The problem I have is that the failsafes (in low power mode) begin from about 5 km. and beyond 8 km. flying becomes dangerous.

I have integrated the Rx. antenna inside the tail, so basically, the antenna is surrounded by balsa, some hardwood (2 mm), and monokote. The lower part of the antenna (about 3 cm.) is inside the fiberglass fuselage of about 1.2 mm. thick.

Could monokote/balsa/hardwood shield so much, resulting in such a dramatic change in range?

The horizontal stabilizer has a carbon fiber rod (5 mm hollow), but it goes perpendicular to the antenna and does not come closer than 5 cm. (I avoided the use of carbon fiber in the vertical tail for obvious reasons). But still, could this affect the range so much?

The failsafes occur when turning (gently), especially at the moment when the plane is at 90 degrees to the base, i.e. when the horizontal stabilizer rises (the side which is closer to the base) and obscures the tail, and less when the hor. stabilizer is lower. Also I have noticed that it occurs when flying directly towards the base, i.e. when the fuse is between the Tx and the Rx antenna. All this suggests to me that there is shading, but from what I understand, it should not occur...

When a failsafe occurs, the RSSI voltage drops suddenly, for instance, at 5 km. I might have 1.6 - 1.8 V, then suddenly it drops within a second to 1.2 - 1.0 - 0.8 and then recovers to the same level. The 1.6-1.8 Voltage is quite similar to what I had with the previous plane at the same distance, but I ahve never had these drop-outs.

Some additional details: The Dragon Link Receiver is near the tail; the video is 5.8 Ghz 600 mW, separated by 60 cm. from receiver , camera Turnigy (shielded, metallic) 70 cm., ESC 80 cm., UBEC 60 cm., OSD Arkbird 70 cm. There are two servos (non-digital) quite close: 6 cm...

Any input would be very appreciated...