One of my \u201clong distance\u201d Fun Flight methods starts\u00a0with a daybreak flight\u00a0into<\/span>\u00a0the prevailing wind. I have found that by doing this I am able to sustain minimal headwind resistance. By maintaining a “nap of the earth” flight plan the headwind is of relatively little significance. Testing of this concept has proven that winds of 20 to 25 mph measured even as low as 500 feet AGL (Above Ground Level) are reduced to no more than 5 mph at Ultralight Flight Level 75 (that would be 75′ above the ground<\/em>). Sometimes there is no measurable headwind at this low altitude AT ALL. This only works early in the morning. I have found that the headwind combines with rising thermals at roughly 10:30 am on, causing the favorable “near earth boundary layer” phenomenon to disappear. Thus these trips become “dawn patrols” in order to take advantage of these elementary physical principles.<\/p>\n Then on the return flight, the rising velocity and building thermal activity allows me to \u201cride the wind\u201d on my return trip. \u00a0It\u2019s like saving desert until the end of the meal.<\/p>\n A<\/strong>\u00a0Practical Aspect<\/strong>\u00a0of it is that this method also helps to insure against the possibility of fuel starvation on the way home.\u00a0You know, having made your outbound destination when fighting the light headwind, that the same (re-filled) fuel tank will get you homebound riding a faster tailwind.<\/p>\n Riding The Wind<\/strong><\/p>\n Now you know why I call myself The Sky Surfer<\/strong>.<\/p>\n A permutation of this method is the Crosswind Journey<\/strong>. As I watch the wind direction trend during the week preceding the flight, I pick out a destination that will provide a course as close to 90 degrees off the wind. This way I can reduce the effect of the wind in either direction. This Fun Flight Method is more problematical than the<\/p>\n Years ago I was given a\u00a0“naturalistic observation”<\/em>\u00a0that provided some of the basis for my\u00a0Long Distance Ultralight Flights<\/strong>. I was in my\u00a0backyard<\/strong>\u00a0with my\u00a0dogs<\/strong>. The\u00a0wind<\/strong>\u00a0was about\u00a020 miles per hour<\/strong>\u00a0from the South with\u00a0gusts to 30<\/strong>. It was\u00a0windy<\/strong>\u00a0enough that the\u00a0birds<\/strong>\u00a0were\u00a0sitting<\/strong>\u00a0it out. Out of the corner of my\u00a0eye<\/strong>\u00a0I saw a\u00a0small, bright, yellow object<\/strong>\u00a0making its way across the\u00a0face<\/strong>\u00a0of my\u00a0fence<\/strong>. It\u00a0bobbed<\/strong>\u00a0up and down and side to side but maintained a\u00a0constant<\/strong>\u00a0movement<\/strong>\u00a0forward<\/strong>\u00a0into the\u00a0wind<\/strong>. It was a\u00a0butterfly!\u00a0<\/strong>By all rights, it should\u00a0not<\/strong>\u00a0have been able to\u00a0fly<\/strong>\u00a0in that wind\u00a0at all<\/strong>, much less make\u00a0headway<\/strong>\u00a0against it. At first I assumed it was\u00a0only able to make forward motion<\/strong>\u00a0while being partially\u00a0shielded<\/strong>\u00a0by the fence. The\u00a0fence<\/strong>\u00a0was\u00a0North\/South<\/strong>\u00a0–\u00a0in line with the wind<\/em>\u00a0– but I decided it was shielding the little creature somehow. Then,\u00a0amazingly<\/strong>, the butterfly\u00a0flew<\/strong>\u00a0above the top of the fence and\u00a0kept going<\/strong>\u00a0though an area with many\u00a0bushes<\/strong>\u00a0and\u00a0trees<\/strong>\u00a0reaching altitudes of\u00a02o to 30 feet<\/strong>\u00a0until it disappeared\u00a0behind<\/strong>\u00a0the\u00a0trees<\/strong>.<\/p>\n I noticed when it was\u00a0clear<\/strong>\u00a0of the\u00a0fence<\/strong>\u00a0its\u00a0“zig-zagging”<\/em>\u00a0increased<\/strong>\u00a0in\u00a0amplitude<\/strong>\u00a0but its\u00a0forward motion<\/strong>\u00a0continued\u00a0unabated<\/strong>. I pondered this for some time.\u00a0Since then I have\u00a0witnessed<\/strong>\u00a0other<\/strong>\u00a0butterfly flight\u00a0demonstrations<\/strong>\u00a0of this sort and have drawn some\u00a0conclusions<\/strong>.<\/p>\n In the\u00a0study<\/strong>\u00a0of\u00a0aerodynamics<\/strong>\u00a0or\u00a0fluid mechanics<\/strong>\u00a0is the\u00a0concept<\/strong>\u00a0of a\u00a0boundary layer<\/strong>. In the context of\u00a0aircraft<\/strong>, this describes the\u00a0air<\/strong>\u00a0layer<\/strong>\u00a0that is\u00a0“attached”<\/em>\u00a0or\u00a0“viscous”<\/em>\u00a0to the\u00a0object<\/strong>\u00a0near it – generally a\u00a0wing<\/strong>,\u00a0propeller<\/strong>\u00a0or\u00a0fuselage<\/strong>. What it tends to do is to\u00a0“grab on to”<\/em>\u00a0and\u00a0“distort”<\/em>\u00a0the on-coming, non-viscous\u00a0air mass<\/strong>. Most study of this effect regards\u00a0high airspeed<\/strong>\u00a0and has been conducted to enhance the ability of\u00a0high performance aircraft<\/strong>\u00a0to cut through the air with\u00a0less drag<\/strong>. I can’t remember seeing anything about\u00a0boundary layers<\/strong>\u00a0at\u00a0low<\/strong>\u00a0air speeds. But, as I thought about it, it\u00a0seemed obvious<\/strong>\u00a0that the\u00a0butterfly<\/strong>\u00a0was making use of\u00a0boundary layers<\/strong>\u00a0at relatively low air speeds. In\u00a0windy conditions<\/strong>\u00a0there is a\u00a0boundary layer<\/strong>\u00a0around\u00a0all<\/strong>\u00a0types of\u00a0objects<\/strong>. In the case of the\u00a0butterfly<\/strong>, his objects of interest are\u00a0trees<\/strong>,\u00a0bushes<\/strong>,\u00a0tall grass<\/strong>, and\u00a0fences<\/strong>. Because the\u00a0wind<\/strong>\u00a0inside the\u00a0boundary layer<\/strong>\u00a0is “viscous” and therefore\u00a0considerably slower<\/strong>\u00a0than the\u00a0greater<\/strong>\u00a0moving\u00a0air mass<\/strong>\u00a0around it, the\u00a0butterfly<\/strong>\u00a0was able to make\u00a0headway<\/strong>\u00a0by\u00a0flying<\/strong>\u00a0through the\u00a0slower<\/strong>\u00a0moving\u00a0boundary layers<\/strong>\u00a0around the\u00a0trees<\/strong>,\u00a0bushes<\/strong>\u00a0and\u00a0fence<\/strong>. Thus, while he\u00a0appears<\/strong>\u00a0to be flying forward against a\u00a0strong wind<\/strong>, he is actually making\u00a0decent headway<\/strong>\u00a0by flying through\u00a0relatively slow boundary layers<\/strong>\u00a0attached to these\u00a0objects<\/strong>.<\/p>\n Harry Callahan<\/strong><\/a>\u00a0wasn’t talking\u00a0airplanes<\/strong>\u00a0when he\u00a0uttered that line<\/strong>\u00a0but the\u00a0wisdom<\/strong>\u00a0is well taken. A\u00a0lot of pilots<\/strong>\u00a0would rather think of themselves as a\u00a0Golden Eagle<\/strong>\u00a0when flying. That really\u00a0misses the point<\/strong>\u00a0for\u00a0Ultralight Flying<\/strong>. Taking inspiration from the\u00a0Boundary Layer discussion<\/strong>\u00a0above, if you are an Ultralight Flyer<\/strong>, it is far more useful to\u00a0think<\/strong>\u00a0of yourself as a\u00a0butterfly<\/strong>.\u00a0Ultralights<\/strong>\u00a0have everything in\u00a0common<\/strong>\u00a0with them:\u00a0low wing loading; lots of drag; relatively low power<\/strong>. A few years back, I\u00a0adjusted<\/strong>\u00a0my\u00a0mind<\/strong>\u00a0to this. After that my\u00a0Ultralight Flying<\/strong>\u00a0experience made a\u00a0quantum leap<\/strong>. It has become far\u00a0more<\/strong>\u00a0interesting<\/strong>\u00a0and\u00a0challenging<\/strong>. Now it is more like\u00a0airborne judo or kung fu<\/strong>. Now I\u00a0don’t<\/strong>\u00a0take the\u00a0hit<\/strong>\u00a0straight on<\/strong>.\u00a0I\u00a0allow<\/strong>\u00a0it<\/strong>\u00a0to move\u00a0past me<\/strong>.<\/p>\n Here’s how that<\/b>\u00a0plays out.\u00a0I stay extremely\u00a0low<\/strong>\u00a0and when possible fly\u00a0around<\/strong>, rather than over,\u00a0hedgerows<\/strong>. It\u00a0works well<\/strong>\u00a0and has permitted me\u00a0much farther range<\/strong>\u00a0on the limited fuel I can carry. But, if you try this, don’t forget that\u00a0Butterfly Boundary Layer Flying<\/strong>\u00a0can only be done\u00a0if you have\u00a0good\u00a0“stick & rudder”<\/em><\/a>\u00a0chops<\/strong>\u00a0and\u00a0maintain<\/strong>\u00a0constant vigilance<\/strong>\u00a0lest one of the\u00a0objects<\/strong>\u00a0adjacent to the\u00a0boundary layer<\/strong>\u00a0reach out and\u00a0smite<\/strong>\u00a0thee<\/strong>.<\/p>\n","protected":false},"excerpt":{"rendered":" Flying Out Into The Wind One of my \u201clong distance\u201d Fun Flight methods starts\u00a0with a daybreak flight\u00a0into\u00a0the prevailing wind. I have found that by doing this I am able to sustain minimal headwind resistance. By maintaining a “nap of the earth” flight plan the headwind is of relatively little significance. Testing of this concept has […]<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":10,"comment_status":"open","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-5768","page","type-page","status-publish","hentry","post-seq-1","post-parity-odd","meta-position-corners","fix"],"_links":{"self":[{"href":"https:\/\/www.fitzvideo.com\/skysurfing2\/wp-json\/wp\/v2\/pages\/5768","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fitzvideo.com\/skysurfing2\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.fitzvideo.com\/skysurfing2\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.fitzvideo.com\/skysurfing2\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fitzvideo.com\/skysurfing2\/wp-json\/wp\/v2\/comments?post=5768"}],"version-history":[{"count":12,"href":"https:\/\/www.fitzvideo.com\/skysurfing2\/wp-json\/wp\/v2\/pages\/5768\/revisions"}],"predecessor-version":[{"id":9670,"href":"https:\/\/www.fitzvideo.com\/skysurfing2\/wp-json\/wp\/v2\/pages\/5768\/revisions\/9670"}],"wp:attachment":[{"href":"https:\/\/www.fitzvideo.com\/skysurfing2\/wp-json\/wp\/v2\/media?parent=5768"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Flying Back With The Wind<\/h4>\n
Crosswind Journeys<\/h4>\n
Aerodynamic Observation (The Butterfly Method)<\/em><\/h4>\n
Boundary Layers<\/a><\/h4>\n
A Man Has To Know His\u00a0(Machine’s)<\/em>\u00a0Limitations<\/h4>\n