Mesin Jet (Aircraft Power Plant)

Pesawat terbang, adalah salah satu obyek yang selalu menarik untuk disimak. Kali ini kita akan melihat perkembangan salah satu “organ vital” pesawat terbang yaitu mesin pendorong yang berjenis mesin Jet atau dalam dunia penerba­ngan biasa disebut Aircraft Power Plant

Mengapa disebut sebagai “organ vital” tentu saja…mesin Jet ini ibarat organ jantung pada manusia yang berfungsi mengatur denyut nadi, juga tekanan darah, yang secara umum pada akhirnya menentukan kelangsungan hidup manusia itu sendiri.

Apabila jantung manusia berhenti, maka seluruh kegiatan kehidupan yang ditunjang olehnya juga akan berhenti. Begitupun dengan mesin pesawat terbang. Apabila mesin itu mati karena suatu hal, maka secara umum sistem internal di dalam pesawat itu akan terancam kelangsungan hidupnya. Hal ini disebabkan karena mesin itu menyediakan fungsi sistem-sistem internal yang ada di dalam pesawat terbang tersebut. Sistem apa sajakah itu?

Sistem-sistem tersebut adalah Sistem Kelistrikan (Electrical System), Sistem Hidrolis (Hydraulic System), Sistem Tekanan Kabin (Pressurization System), Sistem Kendali Pesawat Terbang (Flight Control System), serta sistem-sistem sekunder lain yang ada dalam pesawat terbang.

Roda pendarat sangat tergantung dengan adanya Sistem Hidrolis ini.Penumpang di dalam pesawat terbang sangat tergantung dengan keberadaan sistem tekanan kabin, agar dapat bernapas dengan leluasa serta normal seperti layaknya diatas daratan.

Sang penerbang pun sa­ngat tergantung dengan sistem kelistrikan, supaya alat navigasi, alat komunikasi, serta alat-alat penunjuk lain dapat diandalkan. Sehingga dapat dibayangkan seandainya mesin pesawat terbang tersebut berhenti bekerja, maka semua sistem diatas akan berhenti juga. Itulah sebabnya mesin pesawat terbang mempunyai peran sebagai “organ vital”.

Dahulu saat pesawat terbang berhasil dibuat oleh Wright bersaudara, satu-satunya tenaga penggerak dan pendorong adalah mesin sederhana yang menggerakkan baling-baling.Baling-baling itu lalu menimbulkan daya dorong (thrust), yang didukung oleh profil tertentu sayap pesawat, sehingga menimbulkan gaya angkat (lift ). Gabungan dari daya dorong dan gaya angkat itulah yang membuat pesawat terbang mampu mengudara seperti yang kita lihat.

Tentunya dua gaya itu harus lebih besar dari dua gaya “lawannya”, yaitu gaya berat (weight) dan hambatan(drag). Seiring berjalannya waktu, mesin berbaling-baling dirasakan tidak mencukupi lagi kebutuhan manusia untuk dapat menikmati pesawat terbang. Hal ini disebabkan pesawat berbaling-baling (Propelled Aircraft) memiliki keterbatasan dalam hal ketinggian jelajah, pemborosan bahan bakar, jarak tempuh, serta waktu tempuh penerbangan. Para insinyur penerbangan ingin membuat pesawat terbang yang mampu menjelajah pada ketinggian yang optimal sekaligus menghemat bahan bakar, memanfaatkan massa udara yang sedikit untuk dimampatkan lalu menghasilkan daya dorong yang spektakuler, serta mampu menempuh jarak yang cukup jauh dengan waktu tempuh yang pendek. Terdengar hampir mustahil memang. Namun, para insinyur pe­nerbangan bersungguh-sungguh ingin mewujudkan keinginan itu. Untuk memenuhi “ambisi” ini, maka dibuatlah mesin Jet.

Prinsip Prinsip Daya Dorong Jet

Apa arti Jet sebenarnya? Darimana konsep Jet itu berasal? Siapakah manusia pertama yang menemukannya? Jet artinya pancaran atau semprotan.Konsep reaksi Jet pertama kali dipercaya oleh para ilmuwan dari sebuah alat permainan di negeri Romawi kuno yang dikenal dengan sebutan Hero’s Engine. Alat permainan ini dipercaya dibuat pada masa 120 tahun SM. Alat ini menggambarkan bahwa gaya/momentum (berupa uap) yang dikeluarkan oleh mulut Jet itu mampu menghasilkan reaksi yang sama besar dengan daya dorong Jet itu sendiri.Kedua Jet kecil itu memancarkan tekanan yang berakibat kedua Jet itu bergerak berputar putar. Kemudian hasilnya Hero’s Engine-pun berputar oleh dorongan kedua Jet itu.

Ilmuwan Fisika terkenal, Sir Isaac Newton juga merumuskan dalam hukumnya yang ketiga, hukum Aksi dan Reaksi. Hukum itu menyatakan “Setiap gaya yang beraksi pada suatu benda, akan menghasilkan reaksi gaya yang berlawanan arah yang sama besarnya”. Dari sinilah para insinyur penerbangan memulai bekerja menciptakan suatu Mesin Jet yang menjadi tenaga pendorong pesawat terbang.

Tahun 1913 seorang insinyur Perancis bernama Rene Lorin, mematenkan sebuah konsep Mesin berdaya dorong Jet. Tetapi ini ternyata barulah sebuah teori, karena pada masa itu belum ada manufaktur atau produsen yang mampu membuat mesin Jet yang berdasar pada teori ini, meskipun saat ini ternyata Ram Jet(salah satu metoda mesin Jet modern) menggunakan konsep Lorin ini.

Tahun 1930 Frank Whittle dipercaya telah mematenkan karyanya, yaitu sebuah mesin gas turbin yang menghasilkan daya dorong Jet. Tetapi inipun masih berupa teori juga. Mesin gas turbin ini baru selesai sebelas tahun kemudian olehnya melalui uji terbang terlebih dahulu.Konsep mesin gas turbin bertipe Turbo Jet buatan Frank Whittle ini kelak dipakai oleh salah satu manufaktur Mesin Jet terkemuka di dunia yaitu Rolls-Royce Welland.

Beberapa Metoda Daya Dorong Jet

Semua jenis mesin Jet sebetulnya sama. Yaitu sama-sama dihasilkan dari bahan bakar dicampur udara yang telah dimampatkan lalu dibakar, sehingga menghasilkan energi berupa daya dorong untuk terbang. Perbedaannya hanyalah pada “cara memasak” bahan bakar plus udara dan pembakarannya saja. Cara memasak diatas disebut Metoda. Bebe­rapa Metoda itu adalah Ram Jet,Pulse Jet,Rocket,Gas Turbine,Turbo/Ram Jet atau Turbo Rocket.

Masing masing metoda daya do­rong Jet diatas memiliki keunggulan dan kekurangan sendiri-sendiri.Tergantung tujuan dan keperluan penggunaannya. Untuk kepentingan pesawat terbang militer tentunya berbeda dengan kepentingan pesawat komersial.

Pesawat Jet militer (fighting aircraft) membutuhkan karakteristik mesin Jet yang tangguh, lincah, fleksibel, dan bertenaga besar untuk mengejar dan memburu lawannya, sekaligus berkelit dari incaran lawan. Sementara itu, pesawat Jet komersial (Jetliner) memerlukan mesin Jet yang dapat diandalkan pada beberapa keadaan cuaca yang terkadang buruk, mudah dioperasikan saat keadaan abnormal apalagi darurat, irit bahan bakar, biaya perawatan yang murah dan mudah, disamping memiliki kemampuan menanjak yang optimum. Dalam hal ini pilihan tentang jenis atau metoda mesin Jet se­perti diatas menjadi sangat penting.

(source)

Balap Motor

Di Indonesia balap motor sudah di kenal semua kalangan, dari anak kecil sampai yang tua pun tau apa itu balapan, terlebih lagi hampir setiap minggu terdapat event balap motor sekelas tarkam (antar kampung).

Di dunia balap motor sendiri terdapat 2 kategori yang di lombakan, Road Race dan Off Road. di Road race sendiri terdapat banyak kategori dan kelas yang di lombakan, yang akan saya jelaskan nanti.

Di dunia  Federation Internationale de Motorcyclisme (FIM) adalah badan Internasional yang berfungsi menaungi berbagai jenis kegiatan-kegiatan olah raga balap motor tersebut.

Karena banyak terdapat bermacam jenis dan bentuk motor, maka terdapat pula bermacam jenis pelombaan dan kejuaraan balap motor, antara lain:

Road Race atau balap jalanan dalam bentuk murni atau asal mulanya adalah balapan yang dilombakan di jalan umum, seperti lintasan Isle of Man TT (Tourist Trophy), Grand Prix Macau dan beberapa lintasan di Ireland. Karena disebabkan oleh bahaya yang tak terlepaskan dari jalan raya seperti jalur sempit, trotoar jalan, dan tembok-tembok, umumnya balap jalanan sekarang dipindahkan ke lintasan-lintasan yang dibangun khusus.

Circuit Racing atau balap sirkuit , yaitu dimana motor-motor balap yang dirancang khusus atau motor-motor produksi masal yang dimodifikasi bersaing satu dengan lainnya di sirkuit yang juga dirancang khusus. MotoGP adalah contoh dari balapan kelas puncak yang melombakan motor yang dirancang khusus untuk balap dan tidak dijual bebas, sementara World Superbike adalah contoh balap yang melombakan motor produksi masal dan dijual bebas namun dengan modifikasi sesuai ketentuan.

Classic Racing Balap klasik adalah dimana para peserta membalap dengan menggunakan motor yang telah dimodifikasi secara besar-besaran dari era awal – biasanya motor-motor sebelum pertengahan tahun 70-an.

Motocross dan sepupunya supercross di lombakan di lintasan berlumpur, biasanya menampilkan motor yang melompat melewati jarak yang jauh.

Supermoto adalah gabungan antara balap jalanan dan motokross. Motor yang digunakan umumnya adalah jenis motor motokross dengan ban motor balap jalanan. Lintasan yang digunakan untuk perlombaan juga campuran antara jalanan dan lintasan berlumpur atau tanah.

Speedway dan speedway es adalah balapan yang diadakan di sirkuit berbentuk lonjong (oval) dimana para pembalap berlomba dengan gaya khas speedway yaitu mengepotkan (membelok dengan menggeser roda belakang) motor untuk memudahkan melewati sirkuit yang hanya berbentuk oval tersebut.

Ketahanan motor (Enduro), dimana balapan di lombakan dalam jangka waktu yang panjang, dan dengan lintasan alam, bahkan melewati daerah terpencil. Reli Paris-Dakkar dan Six Day Endurance adalah contohnya.

Trial Motor di mana peserta mengendarai motor yang dbentuk khusus dengan berat yang ringan dan dengan suspensi yang fleksibel. Peserta harus menaklukkan beragam rintangan buatan seperti kotak, ban, tong yang bertumpuk dan rintangan-rintangan lain. Lomba juga dilakukan di rintangan alam berupa batu-batuan. Peserta di haruskan melewati rintangan-rintangan dengan kesalahan seminimal mungkin untuk menjadi juara.

Drag Race motor (juga dikenal dengan sprints) dimana dua peserta start di belakang sebuah garis star yang sama dengan tanda star berupa lampu. Setelah lampu star menyala dua pembalap memacu motornya melewati dua lintasan lurus sejauh seperempat mil, dimana waktu tempuh mereka di catat dan di hitung. Pembalap dengan catatan waktu paling singkat melewati garis finis adalah pemenangnya.

Hill Climb adalah dimana seorang pembalap menaiki atau mencoba menaiki sebuah bukit berlumpur atau tanah dengan motornya. Motor yang digunakan di rancang khusus dengan lengan ayun (swing arm) yang panjang dan ban khusus ala motokross. Pembalap yang mencapai titik tertinggi di bukit atau tercepat menaiki bukit adalah pemenang.

Land Speed dimana seorang pembalap tunggal memacu motor melewati sebuah lintasan lurus sepanjang satu sampai tiga mil (biasanya dilakukan di permukaan sebuah danau yang mengering) Pembalap tersebut harus berupaya untuk membuat catatan waktu tercepat dan melewati catatan rekor pembalap sebelumnya di kelas tersebut atau berdasar jenis motor yang dipakainya, agar namanya tercatat dalam buku rekor.

Drag Bike History

Biography Black History Month
By Keith S. Kizer
Photos by: James Pratt, Matt Polito, and unknown.

As much focus is put on civil rights leaders such as Dr. Martin Luther King, Thurgood Marshall and Shirley Chisolm during Black History Month, I would like to take this opportunity to recognize some of the men and women who made their mark on the sport of motorcycle drag racing. I’ll beg forgiveness now for the many names that are missing from this list. I’ve tried my best with my limited thirty-year history, which mostly spans IDBA and Prostar events. Also thanks to Leshon Norman, Marc Powe, Tommy Bolton, and Doug Frierson for their help in assembling these pioneers of drag racing as we celebrate Black History Month.

One of the first to pioneer the sport was Joey Norman from who was the first black to race Top Fuel in 1972 on a Harley.

In the mid 80’s Bill Timmons was featured in Hotbike magazine as an IDBA record holder in B Altered Turbo. Bill had a sit up street version of his B/AT bike that was known as the fasted streetbike in Ohio. Bill started racing with IDBA in 1978. He eventually raced Funnybike and earned as high as the #4 plate with IDBA in 1986.

Another noted Funnybike great was Bernard King from Pompano Beach, Florida. In 1984, Bernard qualified #1 in Funnybike at the IDBA Spring Nationals in Gulfport, Mississippi with a 7.86 ahead of Terry Kizer. The two met in the finals with Bernard taking the win. This was the first time that an African American had both qualified #1 and won the event in a professional category. Bernard was also the first black to compete in Funnybike.

If you are looking for an innovator in promotion of motorcycle drag racing, look no farther than Tim Mills of the “Dash for Cash” series. In 1980, Tim bought the first GS1100 Suzuki sold in central Indiana and immediately starting racing it. That led Tim to producing an all motorcycle drag race with a larger purse than IDBA or Dragbike were paying. And since Dave Schnitz is the sponsor of this column, it is worth noting that he was the only white guy that raced at Tim’s first event. Thanks Dave, that was very white of you. The event grew to an average of over 200+ bikes competing in bracket racing with a high attendance of 322 one year. The series ran until 1996. During that time Tim was also a winning competitor in both IDBA and Prostar in Pro ET and Super Comp. This year marks the return of the “DASH” with the Dash for Cash Reunion set for May 30th at Muncie Dragway.

SEMDRA’s Doug Frierson started drag racing at famed Orange County Dragway in Southern California back in 1973 while stationed in San Diego with the Marines. His bikes known as “The Leatherneck Express” carried him from one the first Top Gas bikes in the sport to Funnybike. Doug is a founding director of the South Eastern Motorcycle Drag Racing Association.

Speaking of founding fathers of SEMDRA, non-will be remembers as well as the late Randy Stevens. Simply one of the nicest guys who ever walked this planet. Randy was also a pioneer in the Pro Mod class for Prostar. He won the #3 plate in Prostar Pro Mod 1995 which also earned him the Pro Rookie of the Year honors. He was taken from this earth way too soon. Randy did leave a mark on this sport through the many racers he groomed and assisted in their careers, Barry Sanders, Terry Wynn, Barry Green, Carlos Wilkerson, J.P. Mattox, David Martin

Other Pioneers

Andrew Abney – Earned three top ten plates in Prostar Superbike from 1996-1998.

Anthony Anderson - West coast racer, ran pro-stock motorcycle also pro street in the 80′s.

Tommy Bolton - Originally from the West coast and claiming wins in Pro Stock, Pro Mod, Pro Street and Funnybike. First black to win mulit-championships in one year in drag bike USA in the 80′s. 1st to run 200mph in FB Championships. Founder of PMRA.

Highway Joe Branch - Earned two top five Prostar Super Mod plates in 1990 & 1991.

Antron Brown - Debuted in Pro Stock motorcycle racing when cousin and famed NFL football player, Troy Vincent sponsored his career in both NHRA and Prostar in 1998. In his rookie year, he earned a #7 plate in NHRA and a #10 plate with Prostar (on a limited Prostar schedule.) In 2000 Antron won the covited U.S. Nationals in Indy. The following year he earned the #2 plate in NHRA. In 2006 he joined the Mickey Thompson 6-second club. In 2008 he successfully transitioned to Top Fuel from PSB with immediate success becoming the only driver in NHRA history to win in Top Fuel and Pro Stock bike.

Randolph Brown - Maryland International Raceway star with over 500 rounds wins to his credit in bracket racing. Also earned top ten plate in Prostar Super Comp in 1992. Last year, Brown was featured on Pinks Arm Drops Bikes.

Reggie Cole - Earned Prostar Pro Stock #3 plate in 1996.

Keith Dennis - Simply one of the most talented riders who ever through a leg over a motorcycle. Keith, known as Shine, is recognized for his street racing accomplishments, but his true claim to fame is his accomplishment on the Prostar tour with team owner Joe Marasco. In just over a decade Keith earned three championships ranging from the factory stock appearing SuperSport to the precision of Pro Stock. In all he earned 11-top ten plates with 9 being top five plates, 5 in Supersport (1997, 1998, 1999, 2000 & 2008), 2 in Superbike (1996 & 2003), 3-Streetbike Shootout (1998, 1999 & 2000 and the #1 plate in Pro Stock in 2003.

Bruce “Bad” Dickson - Though known more for what he did not accomplish, Bruce was persistent in his efforts in NHRA and did earn a #8 plate with Prostar in 1995.

Richard Gadson - One of the many racers who grew up around the Prostar pits and started racing careers before they could legally drive. A memorable moment was the “brat pack” trio of Gadson, Ed Murphy and Vince Woska celebrating their eighteenth birthdays and graduation at St. Louis. Actually each of them were far from being brats. They are true ambassadors of the sport. Don’t they look like babies?

Richard earned six top ten plates with Prostar / AMA Dragbike, 2-SuperSport (2003, 2004, 2007), Super Street 2007, AMA Dragbike Super Street 2008, AMA Dragbike Real Street 2009.

Rickey Gadson - If you want to talk about Black history, Rickey Gadson is without question the most decorated who started with Prostar at the inaugural race at Atco in 1989 back in the IHRA days.

Rickey was also the first to earn the honor of fulltime factory rider when John Hoover of Kawasaki hired him to carry the Kawasaki banner for drag racing. To date Rickey has earned 22- top five plates with eight of those being championships. He started in Top Gas in 1990 and earned his first championship a year later in Pro Comp. By class Rickey earned plates as follows: Top Gas #3 in 1990, Pro Comp #1 in 1991, Funnybike #3 in 1993, SuperSport: #1-1996, 2-1997, 2-1998, 3-1999, 2-2000, 1-2005, 1-2009, Superbike: 2 – 1996, 1-1997, 1998, 1999, 2-2000, 2-2001, Streetbike Shootout: 3-2001, 2-2002, 1-2003, 2-2004, Super Street: 2-2007 & 2008, Real Street: 10-2009.

Jesse Gatlin - Former West coast Pro Stock racer, once featured in Black Biker magazine as an up and coming motorcycle and engine builder. His bikes have also been featured in Hotbike.

Olin Gould III - The Gould family was one of the first families of Prostar. Olin III earned three top ten plates in Super Gas from 1999-2001.
Keith Gray – West Coast racer who became the first Black to run a 7-second pass in NHRA.

James Guyton - Prostar Funnybike #8-2003

Lee Hays - West Coast racer who was the first black to win the Dragbike USA Pro Stock championship back in the 1980′s.

Charles Henry - Better known as Z1, ran NHRA Pro Stock in the 80′s.

Japel Heard - Earned Prostar Pro Mod #10-2007

Perry Hollie – Earned ten top ten plates in Funnybike from 2000-2009.

Norman Jackson - Earned three top ten Prostar SuperSport plates from 1999 -2001

Bernard Johnson - Started racing locally in Atlanta in the early 80‘s before moving to IDBA and Prostar racing Top Gas and Pro Comp but settled in Pro Mod which earned him three top ten plates from 1996-2004. Bernard won the SEMDRA Pro Unlimited Championship in 2003. Bernard also won the first two ADRL Pro Mod Championships as a bike owner with Billy Vose riding.

T.T. Jones - Earned two top five Prostar Pro Mod plates in 2007 & 2009. Promotor of series at Huntsville Dragway.

Von Kincannon - Prostar TG #2-1990

Johnny Kirkwood - West Coast Pro Stock racer the late 70′s.

Harry Lartigue - NHRA and IDBA Pro Stock racer started racing professional in 1978 who turned owner/tuner when Pro Stock racing became “a jockey sport” he launched the NHRA careers of other Black racing pioneers Michael Phillips, Reggie Showers, Redell Harris and Peggy Llewellyn.

Peggy Llewellyn - First black female in professional

Russell Love - Prostar Super Mod#1-1990, #2-1991

Ron Marshall - West Coast racer better known as ‘Honda Man”, also one of the pioneers of west coast black race teams back in the 70′s.

Tony McCullin - West Coast Pro Stock racer in the late 80′s later who went on to race the “funny cars”.

Edward McGoo - Mr. McGoo racing teams was one of the first black race teams in the 70′s and 80′s. Tracy McGoo, races now in MDRA.

Buck McPhatter - Earned the Prostar Pro Comp #2 plate in 1990.

Big Kem Minor - Earned two Prostar top ten plates in 1990, Super Gas and Super Mod.

Edward Murphy - Part of the Prostar trio, he earned four top ten plates in the class he started racing in, Supersport from 2003 to 2009. In 2007 he also was the brides maid in Pro Stock. Rounding out three top ten plates in 2007 he also captured a Super Street top ten as well as 2008.

Nathan Murray – West Coast rider who became the first Black racer to run a 6-second pass in PM in Prostar also earning a top ten plate in 1998.

Glen Nickelberry - Midwest rider that teamed up with Tommy Bolton in the mid 90′s making them one of the first Black racing teams who have celebrated 65 victories and three championships together, IDBA in 1999 and PMRA in 2000 & 2001. Glen also made a big impact in the motorcycle drag racing world being the first offically black to run 6 seconds in the quarter mile and the 2nd to run 200 mph at a national event. Earned Prostar Funnybike top ten plates in 2003 & 2004

Jimmie Nichols - Prostar Pro Gas Champion in 1990

Michael Phillips - First Black to win an NHRA PS Bike race, Houston 1995. Michael is one of those in a class of racers like Rickey Gadson and Keith Dennis, who can ride any class and excel. Michael also earned eight top ten honors in Top Gas, SuperSport, Streetbike Shootout and Pro Mod spanning from 1996-2007.

James A. Powe - Early 70’s Gulf Coast street racer who eventually raced Pro Comp and Funnybike with IDBA. His son Marc started racing at the age of 15 and competed in Prostar and SEMDRA and is keeping the Powe drag racing torch burning.

Ray Robinson- Another west coast drag bike racer, ran out of galtin racing.

Reggie Showers - Racer who started his career in secracy while racing in IDBA and Prostar for fear of not being allowed to compete. A racer who was a pioneer in his use of nitrous oxide and the first to utilize an Orient Express 5-speed billet transmission. The combination provided record breaking top speeds that won Reggie the IDBA Pro Comp Championship in 1989. Finally in the early 90‘s Reggie went public as a double amputee after NHRA’s acceptance of handicap racers. Reggie earned a Prostar Pro Comp top five plate in 1990 and a top ten in Pro Stock in 1995. Once in NHRA he earned three top ten plates from 2001 – 2003. Reggie retired from racing following the death of one of his best friends, Brian Schultz who had laid the ground work for his own Pro Stock career following in the footsteps of his late father, Dave Schultz.

Carl Smart - Prostar Top Gas #6-1991

Lloyd Straus - Pro Stock racer.

Coodee Thomas - Prostar Pro Mod #5-2005, #3-2007

Alphonso Thompson - Prostar Streetbike Shootout: #6-2001, #4-2002, #4-2003

Keith Thompson - Prostar SuperSport: #4-2000, #4-2001, #5-2002, #7-2003, AMA Dragbike Real Street: #2-2009

Marvin “Big Thunder” - Was one of the west coast pioneers late in the 70′s.

Ron Weens - First Black to go 7 seconds on “no bar” bike in 1989.

Lester White - West Coast fabricated better known as the “Dragon Fly”, also motorcycle racer.

Chris Williams - Another racer who rivaled the talents of Rickey Gadson, Keith Dennis and Michael Phillips with an outstanding career in Prostar from 1996-2002 earning 11- top ten plates in SuperSport, Superbike, Streetbike Shootout and Hot Rod Cruiser. One of Chris’ most famous moments came during the year that too many Shootout bikes were exploding on the top end. At Indy Chris found himself aboard a flaming motorcycle and made the unbelievable decision to standup on the bike and jump over the concrete retaining wall. Thankfully he did not hit anything on the other side and walked away from the incident as his motorcycle burned to the ground.

Thad Wiltz - West Coast Funnybike racer who earned a Prostar Pro Comp top ten plate in 1991.

Horace Wright - Earned Prostar Pro Stock three top ten plates from 1995-1997

 

this article copied from http://bit.ly/xlCh0S

Nadya Dwi Senjani’ Photos

nah kalo ini sebagian ada di laptop ade gw, nanti maleman gw pindahin dah..

Nadya

 

Sabrina Utami’s Photo

on my flickr.. doh..!!

flickr gw mateee akun pro nya.. nanti tak upload lagi deh

“65th Anniversary TNI-AU”

Menyambut “65th Anniversary TNI-AU” majalah Angkasa bikin edisi Pesawat Kombatan TNI-AU. Di buka dengan cerita: Pd 3 Juli 2003 di Bawean, Laut Jawa, 2 pswat F-16 TNI-AU dual seater bertikai dengan 5 F-18 Hornet US-NAVY dari kapal induk Amerika USS Carl Vinson. 2 F-16 TNI-AU dpiloti Kapt Ian Fuady, Kapt Fajar Adrianto, Kapt Toni Heryanto & Kapt Sastro Utomo.

Ini cerita benar terjadi. Ke-7 fighter ini saling locking & jamming. Syukur tidak sampai ada rudal yg ditembakkan. Kalau terjadi, itu pernyataan perang!

2 pesawat F-16 TNI-AU berhasil menundukkan 5 pesawat F-18 Hornet Amerika. KSAU Marsekal TNI Chappy Hakim menyampaikan apresiasi atas keberanian pilot tempur TNI-AU menjaga kedaulatan RI.

USS Carl Vinson masuk wilayah Indonesia tanpa izin. Amerika seperti biasa merasa itu wilayah internasional yg sebenarnya tdk tercantum di peta pelayaran international. Bagi Indonesia, itu adalah Alur Laut Kepulauan Indonesia (ALKI), sifatnya lintas damai atau innocent passage. Syaratnya, minta izin kpd ATC Ngurah Rai & pesawat yg mrupakan bagian dr kapal atau armada tdk boleh terbang.

Dulu, saya pernah dengar pilot TNI-AU menghalau fighter Australia yg masuk ke wilayah Indonesia. Adegannya mirip film Top Gun. Pilot2 TNI-AU memepet pesawat Australia, mngibaskan kepalan tangan, jari telunjuk & jempol teracung bergantian, mengisyaratkan “You! Get out from here!” Dengan sombongnya pilot Australia memiringkan pesawatny, memamerkn prsenjataannya yg jauh lebih lengkap, berharap pilot2 TNI-AU ciut nyali. Namun, pilot TNI-AU justru menjawab tantangan itu dgn membalikkan pesawatnya & terbang terbalik (inverted) di atas lawannya. Dengan posisi begini, para pilot yg bertikai ini bisa saling memandang & pilot TNI-AU mengacungkan jari tengah kepada musuhnya, “Fuck you!” Sejauh ini, jurus kamikaze benar2 berani mati ini ampuh mmpertahankan kedaulatn RI.

Cerita kberanian pilot2 TNI-AU ini sdh lama & sering saya dengar. Baru sekarang di buka kepada masyarakat. Negeri ini haus crita heroik motivasi untuk membangun dirinya.

Dirgahayu TNI-AU! Bravo Angkasa!

@jiahaha

kojakers di #24Maroon5

RAAAMMMEEEEE…!!!!!
hal itu yang pertama kali melintas di pikiran gw pas dateng ke #24maroon5 bersama Coca-Cola Indonesia.

pas pertama kali masuk, gw langsung ngisi daftar hadir dan kebodohan itu muncul ke permukaan lagi, gw salah ngisi daftar hadir.. ) gw nulis email gw sama blog gw atas nama temen gw @gegepoweranger sampe si mba yang cakep itu ketawa geli. ahahahahaha.. so sorry dude..
abis ngisi daftar hadir yang memalukan di depan mba mba yang cakep itu, kita di kasih swags dari Coca-Cola yang isinya press release, DVD Original Maroon5 (jarang2 gw punya DVD ori), dan baju Coca-Cola. ah ternyata itu baju emang belon rejeki gw, ukuran baju nya S..!! iyeee… badan gw XL..!!

ok lanjut nyari tempat duduk sama @gegepoweranger n @nikonoresha, setelah duduk selama 10 detik kurang, gw sama @gegepoweranger pun langsung ngincer makanan yang ada di prasmanan.. ehehehhe.. enaakk rooyy.. sayang aja gw ngambilnya sedikit..

acara pun di buka oleh Steny Agustaf, sama temen nya entah siapa lupa namanya.. -__-’ setelah peluncuran website resmi Coca-Cola Indonesia http://coca-cola.co.id di lanjut dengan music performance oleh mike (kalo ga salah )

daaaaannnn…… mulai lah keramaian yang di timbulkan kelakuan anak” kojakers.. gilllaaa.. anak” kojakers pada asik2 semua.. yang makin meriah acara #24maroon5. belum lagi @exotrisc yang dapet jam tangan dari Coca-Cola.

ga cuma itu aja loh.. doorprize tiket nonton maroon5 juga di menangkan oleh anak kojak, @dimasnovriandi dapet tiket tersebut.. T.T kapan yaa gw dapet tiket gratis.. T.T

lanjut aja dah gw kasih foto2 anak @kopdarjakarta yang lagi menggila.. link

own lense

Nikon, Canon, Leica, Pentax, Sigma, Tokina, and a host of other lens makers are all striving to bring you the sharpest lenses with all optical aberrations reduced to the minimum. That’s too bad! Because with lenses, as with life, sometimes it’s the imperfections that make things interesting.

The image on the left was shot with the imperfect optics of a homemade lens. Exploring the soft, dreamy world of DIY camera lenses in surprisingly easy. Let me show you.

There are two components necessary for a homemade camera lens suitable for use on a SLR or DSLR: the optics (to focus the light) and the mechanics (to hold the optics in place and hopefully provide a method of adjusting the focus and aperture).

The Optics

Any lens that focuses light (a double convex, plano convex, or positive meniscus) can theoretically be used as a camera lens. Magnifying glasses, lenses from binoculars, close-up “filters,” reading glasses, are all potential camera lenses. A good source for purchasing lenses is Surplus Shed, where they typically cost $4.00 to $10.00. Or for a limited selection (mostly from science class materials) check Amazon.

Notice that I used the word theoretically above. There are limitations. Every lens has its focal length. When a lens is used to focus parallel rays of light, the focal length is the distance from the lens to the point of focus. This means that for a single element camera lens, the focal length determines the distance the lens needs to be from the film or sensor. This is very important for constructing your lens and it puts some limitations on the lenses that are useful. Assuming you want to use your lens with a SLR or DSLR, the focal length can be no shorter than about 45 mm because that is the approximate distance from the lens mount to the film/sensor plane. A lens with focal length shorter than 45 mm would have to be mounted inside the camera to reach proper focus on distant objects. That’s not going to work. At the other extreme, a lens with a focal length of more than about 400 mm starts to get very awkward.

So unless you already know the focal length of your lens, you should measure it. You’ll need a piece of paper, a ruler, and a distant light source such as a lamp across the room (do NOT use the sun for this). Project the light from the lamp through the lens and onto the paper. Adjust the distance between the lens and the paper until the image is at its sharpest. Now just measure the distance from the lens to the image on the paper. This is the focal length of the lens, or close to it. Ideally, the light source should be an infinite distance away, but I find that a light across the room gives me a pretty good approximation. (If you insist on precision, then also measure the distance from the object to the lens and use the formula below)

Depending on how we address the mechanics of the lens, focal lengths in the range of 60 – 200 mm are good candidates for DIY camera lenses.

Starting Simple

Let’s look at some examples, including different ways to address the mechanics.

The first lens uses a positive meniscus from Surplus Shed with an advertised focal length of 65 mm and a diameter of 47 mm (price: $6). As it turned out, Surplus Shed’s measurement of the focal length is a bit off. The actual focal length of this lens turns out to be about 45 mm, so it will not quite focus to infinity. (The flange-to-focal-plane distance of a Nikon is 46.5 mm.) Interestingly, at a diameter of 47 mm, this lens exactly fits in a Nikon lens mount without falling into the camera. And that’s how I use it: by just holding it against the mount with my fingers as I take the shot. It’s not very practical. On the plus side, a 45 mm focal length meant that this lens is theoretically faster than f/ 1.0. And so, I call this lens the antipinhole.

First Results: Optical Aberrations

With the lens resting in the lens mount, the focus is fixed at about 10 feet. The images are about a half a stop brighter than my Nikkor 50 mm at f/ 1.4 so I don’t think it’s quite f/ 1.0 but it is measurably faster than f/ 1.4. But the big surprise is low contrast and very large halos around any bright objects. And unlike what you might expect from a lens at about f/ 1.2, there is no thin plane of focus that snaps in. Instead, there seems to be a very broad area from about 7 feet to 14 feet that has nearly the same degree of focus. Of course, the low contrast, halos, and soft focus can all be put to good use as long as you are not looking for the crisp images produced by commercial lenses.

All of the distortions I mentioned above can be largely explained by the spherical aberration in this lens. Parallel rays of light passing through the lens near the center come to focus as expected at the focal length. However, light rays passing through the lens toward the edge focus at a different distance.

Spherical aberration is the largest cause of distortion on this lens but it is not the only cause. Color fringing (noticeable as blue and/or red fringes at high contrast transitions between black and white) from chromatic aberration is also present, and is caused by the fact that for a lens like this the focal length for short wavelengths (blue) is different than for long wavelengths (red).

Using An Achromat To Address Chromatic Aberration

Chromatic aberration can be significantly reduced by using achromatic lenses, which are made by combining a convex lens made of crown glass with a concave lens made of flint glass. Fortunately, inexpensive achromats are readily available. Binocular objectives are one source. Another is (you guessed it) Surplus Shed, where they sell a wide range of achromats including one with a focal length of 75 mm and a diameter of 53.5 mm.

Once again, spherical aberration resulted in soft, “glowing” images.

Mechanics: Connection To The Camera

The mechanics involved in making lenses is often more challenging than the optics. But you have lots of options. One possibility is to go for a reusable, interchangeable-parts approach. Old style macro extension tubes, such as a set of Nikon K rings, provides a shortcut. One side of the K2 ring mounts to the camera and the other side has a thread that fits 52 mm filters. This 52 mm thread is a convenient standard to use for quickly connecting multiple lenses, spacers, focusers, and diaphragms into a working lens (and then disassembling it for the next experiment). Here is a 75 mm lens along with some aperture rings. Note that the achromat was friction mounted (thanks to a layer of masking tape) to three 58 mm rings that were recycled from some junk filters. A 52 to 58 mm step up ring allows this lens to fit my 52 mm standard.

Adjustable Focus

Although functional, the preceding lens still doesn’t have a mechanism for adjustable focus. Let’s look at a few approaches to solve that problem. The first approach is to “recycle” the helical focuser from an old lens. Mounts and filter threads can be attached with Super Glue if necessary. This lens also includes an old iris diaphragm I found for $3 at a local surplus shop. Attaching rings from junk filters to both the focuser and the diaphragm will allow you to use them in an interchangeable system. This lens uses a 191 mm achromat ($9 from SurplusShed).

Another approach is to use two tubes with slightly different diameters to build a sliding (telescoping) focuser. Cardboard mailing tubes or PVC pipes are possible sources for the sliding tubes. Sticky-back felt, from your local arts and crafts store, can be used to create a nice friction fit between the two tubes. Be sure to leave a lengthwise gap in the felt to allow air to escape as you are focusing. The felt can also be used to line the inside of the tubes to reduce reflected light inside your lens. Here’s an example that uses this approach for a rather improbable 400 mm lens.

If you are lucky enough to have access to bellows, you have an ideal focuser for homemade lenses.

Of course, you can also find more creative ways to mount your optics, such as using a 2 inch steel electrical conduit with a screw-in coupler to make a functioning focuser.

Results

Soft, Misty, Dreamy … you choose the adjective.

Coming up in part two of this series, I’ll show you how you can get control over the glow from the spherical aberration of these simple lenses to produce wonderful soft focus effects or even sharp macro and telephoto images.

Click here for the next part: Homemade Lenses: What’s All The Fuzz About?

John Swierzbin is a photographer obsessed with DIY lenses, if you wish to learn more about them. please visit the Homemade Lens Group as well as his photostream both on flickr. There, you’ll be able to see many more examples of homemade lenses and the images they produce.

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penghinaan terhadap teman wartawan

26 januari merupakan hari yang saya tunggu, karena hari ini merupakan pelantikan walikota depok yaitu Nur Mahmudi Ismail. yaaa.. tau lah NMI siapa, dia adalah walikota periode sebelumnya yg kebetulan memenangkan pemilu tahun ini.

meskipun rumah saya dekat sekali dengan DPRD Depok, saya tetep aja terlambat.. karena harus nganterin ibu negara (dibaca : nyokap alias ibu alias mamah AKA EMAK).

yasudah lah karena ga bisa masuk ahirnya saya ikut ngumpul aja sama teman teman wartawan (gw belom jadi wartawan, jadinya nyari ilmu dulu.. ) nah lagi asik asiknya ngobrol, salah satu teman pers ngasih kabar kalau di margonda ada rusuh, karena ingin ngejar berita kami pun langsung buru-buru ke margonda.

ketika saya di pertigaan pasar, saya melihat teman pers dari info depok yang sedang di teriaki oleh anggota DISHUB DLLAJ Kota Depok  dengan kata-kata yang memang TIDAK PANTAS..!!

langsung saja teman wartawan tersebut menanyakan maksud kata-kata tersebut ke petugas tersebut, saya pun langsung menghampiri petugas itu. dan ternyata petugas tersebut bukannya meminta maaf malah seperti ngajak berantem, yang minta maaf pun atasan nya.

karena kita tidak ingin ketinggalan moment, kami pun melanjutkan perjalanan. meskipun ternyata demo di margonda itu ga ada.. padahal saya udah nyari sampe ke gerbang Depok.. -__-’

akhirnya saya ke walikota depok aja dengan harapan dapat berita. sesampainya saya di walikota, saya agak canggung karena ga ada yg kenal. dengan agak sok tau dan ga tau malu saya pun ngobrol sama wartawan senior.

setelah lama ngobrol saya diajak untuk ke DISHUB untuk jadi saksi petugas yg mengatakan HAL TIDAK PANTAS itu. yaa setelah sampai sana pihak dari DISHUB meminta maaf atas KETIDAK SOPAN SANTUN ANGGOTA NYA DALAM BERTUTUR KATA. yaaaaa.. it’s ok, kami pun dari pihak wartawan memaklumi hal itu. karena kami pikir masalah ini sudah selesai, kami pun kembali ke Pemkot. tapi sayang, teman pers sudah bubar.

akhirnya saya berpisah dengan mba eno dan teman-temannya (lupa euy nama temennya.. ). yah saya pikir ini akhir hari ini, karena panas yang lumayan bikin murka, saya pun niat nyari es podeng.

abis nikmatin es podeng, saya teringat pesen bang Norman kalo nanti di ajakin ketemu dengan kepala DISHUB (lupa namanya). saya akhirnya memutuskan untuk kembali ke kantor DISHUB.

langsung saja, saya di berikan sebuah amplop oleh kepala DISHUB tersebut sambil ketawa ketawa ga jelas.

dengan bingung saya menanyakan untuk apa amplop ini pak?? pak DISHUB menjawab : “yaaa.. ga laahh.. kita kan teman yaaaa…”

apa coba maksudnya??

akhirnya saya membuka amplop tersebut yang isinya 1 lembar berwarna biru alias 50ribu..!! saya sama sekali ga ngerti maksudnya bapak DISHUB ini. kemudian bang Norman bilang “mi, kamu sms bang john kalo kita harus ketemu dan membahas amplop ini” seketika itu juga saya langsung sms bang john.

sayapun langsung kembali ke pemkot bersama mas norman untuk janjian dengan teman pers lainnya. tapi karna banyak yg sedang liputan, saya pun di sms oleh bang john untuk mengembalikan amplop beserta isinya tersebut. saya pun langsung bergegas ke kantor DISHUB.

kebetulan pada saat saya sampai disana bapak kepal DISHUB (pak siapa gitu lupa) sedang mengeluarkan mobil kia carnival nya. langsung saja saya menghampiri dan mengembalikan amplop tersebut.

ini yang saya merasa agak terhina dy bilang : “ikhlas nih di kembalikan?? hoooaaahhh…!!! meskipun saya belum menjadi wartawan, tapi saya merasa ini udah menghina.. huuhh..

oiia..

FYI karna saya lupa nama orang yang ngasih, tapi saya inget dia berlogat sunda, mengendarai mobil KIA CARNIVAL

Membersihkan sensor kamera

hhmmm…

hal yang paling menyebalkan ketika foto langit adalah adanya spot atau titik – titik hitam di hasil foto, hhhoooaaaahhh…. sangat menyebalkan memang..

hhmm.. karena ingin hasil yang bagus dan bersih seperti para fotografer profesional, saya pun penasaran. dengan modal sendal jepit + celana robek, saya pun nekat dateng ke salah satu service centre yg ada di kemang.. hehehe..

setelah di sepanjang jalan di liatin orang + di parkiran di kira tukang parkir, saya pun sampai ke service centre kamera yg terkenal (mahal) itu. dengan nekat bin ga tau malu saya ngasih kamera saya ke mba mba judes yg kebetulan lagi sial melayani saya.