TaiidanTomcat Posted October 28, 2012 Share Posted October 28, 2012 very interesting Link to comment Share on other sites More sharing options...
tropical thistle Posted October 29, 2012 Author Share Posted October 29, 2012 Figuring where to place the advanced turbofanjet reacktors on the Sand Shark's slim and slender frame was not straight forward indeed... In Schwechat, Doktor Siegfried watched the stars for signs... he consulted ancient chinese divination... he even dabbled briefly in voodoo, reading chicken entrails... After endless nights of enforced roast chicken dinners, our totally frustrated doktor decided he simply had enough. He retired early to bed and... proceeded to have the most pleasant dream... He dreamt of participating in a menage a trois... Well not quite an orgy... Sieggie thought it was the delicious Marillenschnäpse he had over indulged in. He woke up to two toothsome Austrian fräuleins, a blonde cuddled up on his left and a brunette snuggled up on his right... It must have been some dream! Eureka! Sieggie suddenly jumped out of bed. He had finally figured out what to do with the advanced reacktors!! Link to comment Share on other sites More sharing options...
TaiidanTomcat Posted October 30, 2012 Share Posted October 30, 2012 Inventive! Link to comment Share on other sites More sharing options...
robw_uk Posted October 30, 2012 Share Posted October 30, 2012 nice - of course Grumman then nicked this design for the Intruder/Prowler setup ;-) Link to comment Share on other sites More sharing options...
tropical thistle Posted October 30, 2012 Author Share Posted October 30, 2012 (edited) of course Grumman then nicked this design for the Intruder/Prowler setup ;-) Nein. Actually Ed Heinemann of Douglas stole Sieggie's ménage a trois configuration. Ed first used it on the F3D Skyknight (the loveable Wille the Whale) in 1948 and subsequently for the cancelled F6D Missiler. Of course, the boys from Bethpage knew a good idea when they saw one and borrowed it for their A-6 Intruder family, but that was much later in 1960. It just proved that the original invention was a stroke of genius... Imdulgence... In moderation (naturally)... of frisky fräuleins... fiery Schnäpse... and other decadent substances... may be highly conducive for work that requires a touch of creativity and invention. Edited October 30, 2012 by tropical thistle 1 Link to comment Share on other sites More sharing options...
Daniel Posted October 30, 2012 Share Posted October 30, 2012 I already like this one a lot, hope you can pull it off Dan Link to comment Share on other sites More sharing options...
oggy4624 Posted October 31, 2012 Share Posted October 31, 2012 Looks like you may have discovered the A9, no points for second place, loser of the JAWS competition. Link to comment Share on other sites More sharing options...
Devilfish Posted October 31, 2012 Share Posted October 31, 2012 Looks like you may have discovered the A9, no points for second place, loser of the JAWS competition. I was about to say the same thing.... Link to comment Share on other sites More sharing options...
tropical thistle Posted October 31, 2012 Author Share Posted October 31, 2012 Shhh.... you two are letting the cat out of the bag. Really, there can only be so many ways to skin a kat... The loser - YA-9 The winner - Su-25 Form follows the function... Sieggie has two constraints. Der Führer does not like Mickey Mouse... Herr Doktor Ernst does not want to be remidned of his bitter rival Willy Messerschmitt... So, the Sand Shark was forced to "evolve". I am traveling from tomorrow night. The downside - werks here will have to be suspended for a couple of weeks, kind of like a two week sabbatical from flugzeug ingenieurbauwerken... The upside - I should have plenty of real time to study actual airliner wings and may be even read up on aerodynamics... t the place I am going to does not serve schnaps... so my R&D may not be as fun as Sieggie's. Link to comment Share on other sites More sharing options...
tropical thistle Posted November 1, 2012 Author Share Posted November 1, 2012 (edited) DOUBLE POST DELETED Edited November 2, 2012 by tropical thistle Link to comment Share on other sites More sharing options...
tropical thistle Posted November 1, 2012 Author Share Posted November 1, 2012 My reading list for the next two weeks: My to do list: Wings Link to comment Share on other sites More sharing options...
Daniel Posted November 4, 2012 Share Posted November 4, 2012 Lots going on, how's the progress? Dan Link to comment Share on other sites More sharing options...
tropical thistle Posted November 6, 2012 Author Share Posted November 6, 2012 Erm, not a lot at this moment Herr Doktor Dan. Stepped away frim das flugzeug werk, considering going back to basics... possibly sift through the sands again to see if anything was missed out in 1939... Also, a trip to a secluded monestary Tibet or Shangri La may be necessary for further R&D werks on the planned mind control weapons systems.. Link to comment Share on other sites More sharing options...
tropical thistle Posted November 21, 2012 Author Share Posted November 21, 2012 Just back from my globe trotting. Can confirm that Confounding the Reich is a cracking read. Not much to report on the jet propelled nightfighter. I have extended the chord of the wings while tweaking the wing sweep slightly, largely retaining the planform of the A-10 - a necessary compromise to achieve the two desired qualities for an interceptor, high attitude aerodynamic efficiency and reduced drag for high speed. l am dreading the putty and sand clean up. Link to comment Share on other sites More sharing options...
trickyrich Posted November 21, 2012 Share Posted November 21, 2012 I feel your pain..... filling and sanding......hours later you wonder if it's all worth it!!! Looking forward to seeing how it progresses. My needs it's help to keep those pesky Ruskies at bay!! Link to comment Share on other sites More sharing options...
tropical thistle Posted November 22, 2012 Author Share Posted November 22, 2012 Gotten morgen, Herr Doktor Siegfried is down with der grippe. I am, Doktor Tiziano Kawalki, your guest vortragende for today’s lecture on aerodynamics. I understand you discussed the planform of the wing yesterday. Today we will explore the effect of varying the chamber of the wing. My uncle, Doktor K.A. Kawalki, at Deutsche Versuchsanstalt für Luftfahrt led a team exploring many different aerofoil and planform profiles in the bid to break the sonic barrier. I was the research intern in some the wind tunnel testing between 1939 and 1940. We found that as the aircraft approaches 80% of the speed of sound, or about 950km/h, the drag from even the most efficient planforms increases exponentially. We tried almost every conceivable configuration, but it really seemed that we had hit an invisible brick wall just below the speed of sound. In a few test cases, the sonic shock wave induced turbulence was so severe that the wing we tested broke up! One day, we had lucky break in the wind tunnel. The technician mounted my uncle's latest configuration upside down on the test stand. Not knowing the wrong placement, we happily ran the totally unremarkable aerofoil section up to a rather remarkable final airspeed of 1,080km/h before we stopped! We thought we finally had our lucky break but could not figure out what was so special about that aerofoil configuration until the brightest bright spark, another research intern, not one of the key aerodynamists, remarked nonchalantly that the aerofoil was secured upside down on the test stand! My uncle and his team continued working further on the optimal aerofoil and planform for near supersonic flight in 1941-1942. Most of his work is still classified as it is geared towards Luftwaffe's next generation jet fighter. I will share with you today a bit of the declassified research data. You see in this diagram, as a typical aircraft's wing approaches 950km/h or there about, the air flow over the chambered top of the wing may already be very close to the speed of sound. If that happens, small localised sonic shock waves will form close to the upper wing surface. These shock waves generate a very turbulent boundary layer just above the surface of the upper wing, thereby generating a disproportionally great amount of drag for the wing. We have tried many, many different wing configuration. Most perform well at lower speed but suffer from excessive drag approaching transonic speed. We found that if you adopt a flat upper wing surface, the air flow over the flat top will be slower than that over a chambered upper surface. We are therefore able to delay the incidence of sonic shock waves after the air flow has passed the upper wing surface. This greatly delays and reduces the drag inducing turbulence as air speed of the wing approaches the sound barrier. We also found that it helps somewhat to reverse chamber the wing or aerofoil on the lower portion of the wing as it is the relative speed of the air flow over the top and bottom of the wing that matters. you however want to do it just right, slowing down the speed of the air flow on top while speeding up the air flow under, at the same time ensuring that there is sucficient lift to keep the aircraft in the air. So, you see, the wind tunnel technician's mistake actually helped us uncover the key to break the sound barrier! So while I believe in vorsprung durch technik, but I also believe in miracles and lucky breaks. Link to comment Share on other sites More sharing options...
tropical thistle Posted November 23, 2012 Author Share Posted November 23, 2012 No update except a status report. With both Herr Doktors Siegfried and Tiziano down with the reader grippe, werks groans to a snail pace. In another time spec dimension, I am also nursing a cold that developed into a what appears to be a very uncomfortable sinus infection. Rest assured that "some" werks continue at the flugzeugwerks. The elfens continue to slave away at putting and sanding. It is an unenviable task - the academy kit is really not bad, but all the modifications and, in particular, der Führer's disdain for mickey's ears have caused much discontent amongst the line crew. Progress is temporarily bogged down, but we hope to bring you some news on Montag. Link to comment Share on other sites More sharing options...
tropical thistle Posted November 26, 2012 Author Share Posted November 26, 2012 The elfens slaved over the weekend polishing the wing surfaces to achieve the lowest drag coefficient. It is a back breaking task, but they managed it with aplomb. We bring you the result of their labour of love. The lovingly polished wings are now the responsibility of Doktor Siegfried , who invited Doktor Tiziano to collaborate with him to formulate the most efficient wing and fuselage interface. The two Doktors poured over the mountain of aerodynamic research papaers and air tunnel testing data collected. They also tried less conventional ways. In the process of the last weekend R&D, Sieggie severely depleted his stash of Schnäpse brought back from his Austrian summer sojourn ... while Tizzie polished off a couple of bottles of his maternal grandfather’s priceless vintage grappa… while I had to stick to the doktor's prescribed antibiotics to clear my clogged sinuses... This was the best we could come up with Perhaps I might revisit this again when my head is clearer... In the meantime, I have to go away for a short trip this week, so the fuselage goes back to the "elfens werks" for puttying and polishing. If all goes well, we will move on (over the weekend) to: 1) reaktor installation; 2) sensory integration; and 3) cockpit fitting out Link to comment Share on other sites More sharing options...
tropical thistle Posted December 3, 2012 Author Share Posted December 3, 2012 Small updates : 1) 2nd round of puttying and polishing successfully completed (elfens threatened strike if more puttying and sanding needed) 2) aerodynamic modification done to central section wing spar... more puttying and sanding (to be done by me!); 3) commenced sensor integration and cockpit fitting... trying to figure out how to find low drag radar aerials; 4) possibly chewed off a bigger piece than I had intended with the fancy reaktormoteurs... yet to figure out most effective way to simulate air intakes and jet exhausts; 5) weapons systems on the drawing board... some form of thought control perhaps; 6) say a silent prayer for completion (of this monster and the little harrier) before Christmas... Pictures to follow after I upload the photos tonight. Link to comment Share on other sites More sharing options...
Col. Posted December 3, 2012 Share Posted December 3, 2012 Look forward to seeing what shape this one is taking. Link to comment Share on other sites More sharing options...
tropical thistle Posted December 4, 2012 Author Share Posted December 4, 2012 (edited) Some photos smuggled out by our undercover agent at Heinkel Flugzeugwerke... Some of stranger things going on in the last two weeks... Herr Doktor Sieggie dabbled in voodoo, the thrifty elfens found a use for the discarded feathers from all the chickens sacrificed. Unfortunately, wind tunnel testing revealed that the chicken feathers do not contribute to overall efficiency at all. Apparently, the drag induced by the feathers significantly outweigh the marginal lift they add... So, the gaps from the amputated mickey mouse ears were plastered with recycled moulding flash from a very old Revell F-16 kit instead. Unfortunately, this in turn brings us to another problem - the elfens are "allegic" to the colour blue, they threatened strike if more puttying and sanding is needed. Nothing else could be done but to expand old fashioned elbow grease for the wicked... And, we have this in the end. Notice the rearward looking radar radome is already installed. Next, Doktors Sieggie and Tiziano worked further to refine the aerodynamics of the wings. My source could not get a better picture at this moment... it seemed suspiciously similar to a supercritical wing of some kind. And, in case you wonder... No, NASA did not invent the supercritical wing. More puttying and sanding looks likely for the wicked... Finally, sensor integration is progressing slowly... Here, you see the mock up of the forward looking radar radome. The radome is not installed yet pending fitting out of the cockpit. I shall show the reaktormoteurwerks in the next installment. Edited December 4, 2012 by tropical thistle Link to comment Share on other sites More sharing options...
Col. Posted December 4, 2012 Share Posted December 4, 2012 This thread does make for entertaining reading and I still have no idea how the finished article is going to look. Link to comment Share on other sites More sharing options...
Daniel Posted December 4, 2012 Share Posted December 4, 2012 and I still have no idea how the finished article is going to look. Nor do I! Dan Link to comment Share on other sites More sharing options...
tropical thistle Posted December 5, 2012 Author Share Posted December 5, 2012 This thread does make for entertaining reading and I still have no idea how the finished article is going to look. Nor do I! Dan Er, actually.... neither do I. That did not prevent me from enjoying this GB (perhaps more fun in writing not so relevant back story than the dreaded sputtying and sanding). Alright, on with the story... I visited Kuwait (even had the ticket stubs to prove it!), but found nothing remained of the sand shark... Apparently, the Germans took every scrap of the aircraft in 1939... I found nothing sifting through the fine sand. Of their resultant R&D (reverse engineeering) windfall, the advanced turbofan reaktormoteur was the most problematic. Largely due the dismal state of metallury, Heinkel-Hirth Reaktor Moteur Werks was only able to replicate the form but not the performance (thrust) and reliability (lifespan) of the GE TF34 turbofan. Although the Heinkel-Hirth copy was only able to achieve a maximum thrust of 21kN instead of 42kN of the real GE engine, this performance was significantly superior to that of Heinkel-Hirth's own HeS011 (bench tested only to a maximum of 12kN). Professor Ulrich Müller, the chief reaktormoteur designer at Heinkel-Hirth's was sufficiently confident of the reversed engineered copy that he convinced her Ernst Heikel to present the cloned copy in place of hsi own HeS011. This reaktormoteur subsequently became known as HeS021. In order to fit the HeS021 into the sand shark, I butchered the fuselage. I confess that I possibly chewed off a bigger piece than I had intended... am still figuring out most effective way to simulate air intakes and jet exhausts. Somekind of seamless intake appears to be required. Prof Ulrich and I tried mocking up with lead foil from good old fashioned White Burgundy... the wine was delicious, but it appears that I keep destroying my prototype seamless intake trunking... in my defense, the lead foil was too soft and malleable. I think I will need another bottle from the cellar.. Some how I don't think the incidental alcohol helped with my picture taking skills, we will have to wait for the fog to settle, perhaps we try again tomorrow... hick Oh, tomorrow I shall introduce you to Herr Doktor Zakharias Zander, the weapons integration guy. I promise you that he would literally blow your mind....hick... excuse me... expand your mind I mean. Ja. Gute Nacht. And, süße träume ... Link to comment Share on other sites More sharing options...
tropical thistle Posted December 6, 2012 Author Share Posted December 6, 2012 A promise is a promise. Ja? I did not manage to solve the seamless air intake yet, but have succeeded in futher mutilating the carcass of the sand shark. In the meantime... Sieben Jahre in Tibet. Mein Leben am Hofe des Dalai Lama Heinrich Harrer was best known as the first European to enter the mysterious land of Tibet. He subsequently wrote a book Seven Years in Tibet. But did you know the story of Doktor Zakharias Zander? Well, I met an elderly gentlemen at a monastery in Kathmandu a few weeks ago. He would not let me take a photo with him. I however have ticket stubs (again!) to prove my visit Nepal. And, this old wise gentleman, who is more than 100 years old, but looked like a youthful 60 year old, played a very interesting part in our story.... Link to comment Share on other sites More sharing options...
Recommended Posts