{"id":178361,"date":"2018-12-22T20:29:00","date_gmt":"2018-12-23T01:29:00","guid":{"rendered":"https:\/\/www.panix.com\/~msaroff\/40years\/2018\/12\/22\/this-is-trippy\/"},"modified":"2018-12-22T20:29:00","modified_gmt":"2018-12-23T01:29:00","slug":"this-is-trippy","status":"publish","type":"post","link":"https:\/\/www.panix.com\/~msaroff\/40years\/2018\/12\/22\/this-is-trippy\/","title":{"rendered":"This is Trippy"},"content":{"rendered":"
<\/a>One sees a number of proposals for using distributed electric propulsion for vertical takeoff and landing systems, but this is without a doubt the oddest concept that I’ve seen yet<\/a>:<\/div>\n

A vertical-takeoff-and-landing (VTOL) design with wings that both tilt and fold<\/a>, providing stable hover and efficient flight, is under development by Boston-area startup PteroDynamics. The company is targeting the military unmanned-aircraft market initially, but has ambitions to develop an air taxi. <\/p>\n

In PteroDynamics\u2019 Transwing concept, the wings tilt and fold back along the fuselage, and the aircraft acts like a multicopter in vertical flight. To transition to forward flight, the wings rotate into horizontal position, allowing the Transwing to fly like a conventional aeroplane. <\/p>\n

\u201cOur vehicle is completely unique,\u201d says CEO Matthew Graczyk. \u201cIt\u2019s 100% fixed wing in horizontal flight and 100% rotary wing in vertical flight, with no compromises.\u201d Unlike a tiltwing, the Transwing can transition between vertical and forward flight with no stall range, he says. The aircraft can have a long wing for cruise efficiency, but folds into a compact size for VTOL. <\/p>\n

\u2026\u2026\u2026<\/p>\n

PteroDynamics has flown a 12-ft.-span model, but has not yet attempted transition between vertical and horizontal flight and does not know how well the design scales. \u201cWe did get lucky with the prototype,\u201d says Petrov. \u201cWhat will happen at 40-ft. or 400-ft. span we don\u2019t know, but as we understand how it works we see no fundamental reason it will not scale.\u201d<\/p>\n

As the wing rotates aft it has more dihedral and sweep and the angle of attack never exceeds 20 deg., while propeller wash helps prevent flow separation. \u201cA tiltwing goes past 45 deg. into wing stall and the wing becomes an obstacle to forward flight,\u201d Petrov says. Transwing \u201ccan stall, but mildly. We tufted the wing and video shows the airflow does separate, but not badly. Mostly the flow stays attached.\u201d <\/p>\n

Petrov describes the tilt\/fold articulation as similar to the wing-fold mechanism on Grumman carrier-based aircraft such as the Avenger and Hellcat, except that Transwing folds leading edge up. The hinge mechanism will carry high loads, but reinforcement of the wing at the fold \u201cshould not penalize the aircraft too much, perhaps 5% of maximum takeoff weight,\u201d he says.<\/span><\/p><\/blockquote>\n

I can’t wait for a full size test.<\/p>\n","protected":false},"excerpt":{"rendered":"

One sees a number of proposals for using distributed electric propulsion for vertical takeoff and landing systems, but this is without a doubt the oddest concept that I’ve seen yet: A vertical-takeoff-and-landing (VTOL) design with wings that both tilt and fold, providing stable hover and efficient flight, is under development by Boston-area startup PteroDynamics. The …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[384,383,382,421],"class_list":["post-178361","post","type-post","status-publish","format-standard","hentry","tag-aviation","tag-helicopters","tag-technology","tag-weird"],"_links":{"self":[{"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/posts\/178361"}],"collection":[{"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/comments?post=178361"}],"version-history":[{"count":0,"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/posts\/178361\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/media?parent=178361"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/categories?post=178361"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.panix.com\/~msaroff\/40years\/wp-json\/wp\/v2\/tags?post=178361"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}