Okay, here's a basic question from someone who knows very little about metal acft construction.
- It's very difficult to quantify the differences between the time/effort needed to build particular aircraft from kits. The hours published by manufacturers are very "squishy" (as they usually admit). But, at the risk of quantifying the unquantifiable, my perception is that these three acft would rate about like this (higher number = more time/difficulty). All from the "standard" kit:
CH 601HD: 5
First--I'd very much like feedback on this assessment. Am I way off? Will an RV-7 take twice as many hours as a Sonex? It just seems that folks accept that it takes most builders 2-4+ years to finish an RV-7, and that builders are getting their Sonex's up in the air in much less time.
Second--why the differences? By most gross measures the planes don't differ that much.
Wing area: RV-7a = 121sft, CH 601HD = 130sft, Sonex = 98sft
Length: RV-7a = 20'4", CH 601HD = 19' 0", Sonex = 18' 1"
Empty weight: RV-7a = 1100 lbs, CH601HD = 590 lbs, Sonex = 620 lbs
(RV-7a: subtract 150 lbs for heavier engine/prop/tires/wheels/brakes/canopy/etc (folks aren't building those things) = RV-7A metal airframe within 35% of weight of Sonex)
Maybe the difference is in the complexity of the structure? The CH 601 doesn't have flaps, so that surely reduces build time somewhat. But the Sonex has all the same components as a RV-7, just 35% smaller. And the installation of instruments, upholstery, etc is going to require the same amount of time for all these planes, given similar levels of finish. And maybe "similar levels of finish" is part of the answer: The Sonex's are flying with basic VFR instruments and the RV-7s have this plus full glass and autopilot.
I've heard good things about customer support from all these companies, and the kits are reportedly well put together (many of the parts have matched-hole construction, etc) and the instructions are relatively clear. It's not like an RV builder is working from a single faded blueprint written in French while the Sonex guys put on virtual reality goggles that lead them through every step--I get the impression that the information is equally clear in all cases.
So, I'd welcome any:
- Input on my wag regarding relative difficulty/time required for these kits?
- Basic explanations for the time differences?
-- Pulled vs solid rivets?
-- "designed for easy building" vs "designed for most refined finished product"?
Thanks in advance.