Sunday, August 12, 2018

Sweet time to reminisce...the days that once were...

[I posted here the post I made in my previous blog in 2013. ]


The Making of the Defiant 300


By Engr. Ernesto Ferreras Jr.

The Defiant under construction...
In 1981 Gold Wings Aviation, a private company under Capt. Panfilo Villaruel Jr. (who later became chief of the Air Transportation Office or ATO and president of Philippine Aerospace Development Corporation or PADC), conceived an aircraft research and development undertaking called the Norlindo Program, named after one of its first engineers. The program covered a progressive development of a high-performance trainer primarily intended for use by the Philippine Air Force or PAF. The program was launched as an innovative step to build an aircraft of local design and utilizing indigenous materials. Gold Wings initiated preliminary design of a twin-engine turboprop named Norlindo and even began conceptual design of a turbojet trainer called Tinihaban Superstrike under the All-Filipino Technology Aircraft (AFTA) Project. Out of these experience, a single, piston engine trainer aircraft was conceived, designed, built and flown within three years.
The Defiant on display during Air Force Day
The Defiant 300 prototype, as the aircraft was called, flew twice, the first on February 22, 1988. The Defiant Projectcame out to be an excellent collaborative effort of a group of aeronautical engineers, aviation enthusiasts, government agencies and research institutions. The two-seat tandem Defiant prototype (registered as RP-X239) was an exceptional technical arrangement of various systems and parts taken from different types of aircraft in the PAF inventory. The landing gears, flight controls and flaps motor were taken from T-34, seats from U-17, rudder and brake pedals rom PT-13, various instrument items from BN-Islander, T-34, Sikorsky S-76 and SF-260. The Defiant was powered by a single Avco Lycoming IO-540-K1B5 piston engine on loan from PADC, the same engine that powers the BN Islander. The prototype had the highest engine power rating of all the prototypes of local design flown so far.

Noteworthy were several original features designed and fabricated by the engines with technical support from several persons and companies. The airframe was fabricated from palosapis wood and the skin from tanguile veneer plywood. The engine mount was fabricated from chrome molybdenum steel. Most significant of all was the fabrication and assembly of a one-piece plastic canopy. Fuel tanks were constructed with 5052-H34 aluminum alloys. Instrument panel, electrical, hydraulic and pitot-static systems were laid out with the help of reference books and articles.

Several companies and agencies gave technical and professional expertise and resources to the project. Pieces of tanguile plywood were procured with the assistance of Forest Products Research and Development Institute or FPRDI; phenol resorcinol glue and its catalyst were provided by Borden International Philippines; paint and primer from Dutch Boy Philippines; line items from the PAF inventory and the hangar for aircraft assembly were provided by Air Force Research and Development Center or AFRDC and the PAF 410th Maintenance Wing; the first plastic canopy was fabricated by RP Plas Sign; the propulsion system was loaned from PADC and initial weight and balance was also performed by PADC personnel. Metal testing and fabrication were done by Metals Industry Research and Development Center (MIRDC). Several consultants from various companies and agencies also contributed to the success of the project.

Based on the successful flights of the prototype, Gold Wings planned to build another prototype of a modified Defiant (appropriately named Defiant 500) with an all-metal airframe and power rating increased to 500 hp. Due to lack of financial support from the government, the plan did not push through however, including another design of a light aircraft called Pegasus, which was presented to the Philippine Army as a contender for the proposed Philippine Army aviation arm.

The Defiant successfully flew in 1988...
With the expertise and experience in aircraft design, prototyping and assembling aircraft accumulated for more than fifty years, we have enough technical resources and manpower to embark on an aircraft prototyping project based on accepted international standards and practices.

Given the rigid requirements in certifying an aircraft prototype for mass production purposes, our local designs never went beyond the prototyping stage. Aircraft assembly of parts never really progressed beyond the prototyping stage. Aircraft assembly of parts never really progressed to fabrication of major parts, like the whole wing, except for the Lancair. We still depend on outside sources.

This continued dependence on foreign sources demands innovative and immediate actions if we are to fulfill the self-reliance concept in aircraft manufacturing. Self-reliance in the aviation industry has become passe in the sense that a succession of government and industry leaders have been mentioning the magic word since the fifties but their efforts have barely lifted aircraft research and development in the country to a self-sustaining and continuing endeavor. The various projects in prototyping our own aircraft began fanfare and copious flow of ideas but all ended in silent frustrations of defeat.


The pace of global technology is so fast that new inventions have cropped up before the current ones are applied to good use. The rate of utilization of these technologies in our aviation industry has been slow, mainly due to large capital investment required.

However, it cannot be denied that we have gained so much expertise and technical know-how in aircraft assembly and fabrication of parts, including aircraft overhaul anbd repair. The employment of competent personnel could be optimized if we could tap them to manufacture, assemble and evaluate aircraft which we will design on our own with the help of new technologies, especially in aircraft design and engineering. We have more than enough manpower and technical and industrial resources, lying dormant these past years, which we could fully exploit and get to move in the right direction.
The Norlindo Team who made it...
Indeed, we are not wanting in local and manpower resources; we have more than enough of it. What we need is the government's commitment to our vision of the future of aircraft research and development in the country.

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