Shameless update from Dale Kramer

On Thursday, March 17, 2016 at 4:19:30 PM UTC-7, DaleKramer wrote:
On Thursday, March 17, 2016 at 6:31:51 PM UTC-4, bumper wrote:
If you used tilting ducted fans, instead of a tilting seat, it would not be as innovative. The ducts would also add drag in horizontal flight compared to folding props. But, if I understand correctly, ducted fans are much less prone to the vortex ring problem.

For this transitional design I think ducted fans would weigh too much, reduce my top speed too much and cause too many structural problems. Tilting fans is what I am trying to avoid ... synchronization issues, tilt mechanism weights, complexity ... I am trying to have a design that people can relate to as 'somewhat' of a conventional airplane shape during cruise.

Dale,

I'm no engineer, but have experienced vortex ring effect caused by too fast a descent into one's own downwash with models, both helicopters and quad-rotors.

I'm guessing vortex ring will be the major design obstacle you'll need to overcome. Consider that in a crosswind, and while maintaining position over the ground descending, the prop wash from the front prop and wing tip props will be moving laterally, so even though they are not positioned in line with, their disturbed air can still conflict with the rear props.

With a limited time envelope to descend and land, there may be considerable pressure on the pilot to descend expeditiously if hand flying. Would this be automated in some manner, or with say a green safe to land "descent profile" indication below a given safe altitude and allowable descent rate, etc.. If, for some reason, the pilot has to abort a landing, say due to wind conditions or surface irregularities, would a vertical take off after a partial descent be possible?

You are on the right track testing with a model, as that should show up any issues.

On Friday, March 18, 2016 at 12:08:46 AM UTC-4, bumper wrote:
Would this be automated in some manner, or with say a green safe to land "descent profile" indication below a given safe altitude and allowable descent rate, etc. If, for some reason, the pilot has to abort a landing, say due to wind conditions or surface irregularities, would a vertical take off after a partial descent be possible?

You are on the right track testing with a model, as that should show up any issues.

Yes there will be automation of some flight maneuvers, after all this could not even be attempted if I was not relying on the multirotor controller for automation of heading and attitude during hover. Adding automated features beyond that is somewhat trivial, especially since I plan to have all control done with 'fly by wire'.

However, I am a firm believer in having a design that is as close to humanly flyable under as many failure modes as possible so I just don't want to start automating things too quickly.

This is a great thread and has given me much to consider, however I am going to have to start concentrating on getting people to pledge on the Kickstarter campaign. If it that campaign fails, I will have to find another way of building the 1/4 scale. So, I will have to slow down the posting here and get my brain into another gear now

DaleKramer wrote on 3/18/2016 5:38 AM:
This is a great thread and has given me much to consider, however I
am going to have to start concentrating on getting people to pledge
on the Kickstarter campaign.

The thread got me to pledge $100. I'm looking forward to seeing the
charge on my credit card next month, which will signal you got the
funding you seek.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "A Guide to Self-Launching Sailplane Operation"

https://sites.google.com/site/motorg...ad-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/...anes-2014A.pdf

Eric,

Thanks for the support!

Dale