Jan 20 2009

Testflights of JSF further behind schedule

Published by JSFNieuws.nl


Kesteren (The Netherlands) - The total test schedule for the JSF includes more than 5000 flights and 11,000 flight hours. This testprogram should be completed at a rate of 8-10 flights per prototype per month. Originally the testprogram would be about 6 years, but has extended again for one year.

In Fort Worth is often thought back with some nostalgia to the successful F-16 program. The first F-16 flew in December 1976. And on January 6, 1979, 25 months later, the first production F-16A was assigned to the 388th Tactical Fighter Wing at Hill AFB in Utah.
The first JSF flew in December 2006, but now 25 months after the start of the testflight program only 1.6% of the flights and 1% of the test flight hours has been achieved.
Though the production has started already, a production representative prototype of the F-35A will not make its first flight before mid-2009. And static (fatigue) tests of a complete F-35A airframe have yet to begin. When any problems will occurs in the testprogram, this may have a major impact on the production line. Also already built and delivered aircraft have to be upgraded with huge financial consequences for the customers. The question is whether in 2010, as planned, the first F-35A really can be transferred to the US Air Force. The first Dutch F-35A aircraft will be the 16th F-35A aircraft that rolls of the production (last F-35A unit of the LRIP-3 series, delivery planned in December 2011).

Status prototype AA-1: again 10 weeks grounded

On December 15, 2006, more than one year later than planned originally, the Joint Strike Fighter prototype AA-1, performed its first flight. The first test year 2007 was not executed in accordance with planning, due to a number of serious malfunctions. Over 7 months the AA-1 was grounded for design modifications and because of engine problems. Indeed. the second test year 2008 was more successful, but again there were four periods each of at least 7 weeks, that the JSF prototype AA-1 could not fly due to several problems and modifications. On November 13, 2008 Lockheed Martin F-35 Joint Strike Fighter JSF proudly reported that the JSF had performed its first supersonic flight. After this milestone, it became quiet again, because since the AA-1 is grounded already 9 weeks again.

To date the AA-1 has a total of 68 flights and just over 95 flight hours. The overall planning for the JSF AA-1 is 100-150 flights.

Overview first JSF pre-production prototype AA-1
Oct-05: original planning in 2002 of first flight
Aug-06: later replanning in 2004 of first flight
Dec-06: 1 (First flight December 15, 2006)
Jan-07 : 6
Feb-07: nul (5 weeks grounded, several upgrades)
Mar-07: 2
Apr-07: 8
May-07: 2 (serieus technisch probleem; hierna 7 maanden aan de grond)
Jun-07 t/m Nov-07: Redesign of several components; problems with engine; see publication “JSF hit by serious design problems, Defense Industry Daily dec-2007)
Dec-07: 4
Total number of flights until end of 2007: 23

Jan-08: 4
Feb-08: 5
Mar-08: 7
Apr-08: 1 (7 weeks grounded due to several upgrades)
May-08: 3
Jun-08: 0 (7 weeks grounded, amongst others due to thermal problems)
Jul-08: 2
Aug-08: 0 (again 7 weeks grounded, thermal problems)
Sep-08: 9
Oct-08: 10 (Edwards AFB testprogram)
Nov-08: 5
Dec-08: 0
Jan-09: 0 (since 13 november again 10 weeks grounded)
Total number of flights until end of 2008: 69
Planning test flights : 8-10 flights per month
Realisation test flights:< 3 per month averaged (30% of target)

Prototype BF-1: grounded since september 2008

The second prototype is a F-35B STOVL type, the BF-1. This prototype performed its First flight on June 11, 2008. However, after only 14 flight the BF-1 is in the hangar to replacing the engine by a redesigned one and to updating several components. Is is expected that in the spring of 2009 the testflights will be resumed. Originally this would occur after 12 weeks, buts ome problems arised with the certification of the redesigned engine, and the restart of the testflight was postponed for some months.

The BF-2 (second STOVL prototype) is in the paintshop this month and is expected to perform its first flight in Februari 2009.

Overview testflights first prototype STOVL-version, the BF-1
Jun-08: 3 (first flight June 11, 2008)
Jul-08: 6
Aug-08: 2 (some flights cancelled, engine problems)
Sep-08: 3 (interruption of test flight program, engine problems)
Okt-08: 0
Nov-08: 0
Dec-08: 0
Jan-09: 0 (still waiting at redesigned, recertificated engine, grounded > 4 months)
Total number of flights until end of 2008: 14
Planning test flights : 8-10 flights per month
Realisation test flights: < 2 per month averaged (< 25% of target)

Is testing confirmation of design only?

One of the principles in the JSF testing is that testing is not “the discovery of problems”, but “confirmation that all the (computer) design is correct.” In principle, it is assumed that no design changes are needed, because of extensive calculations and simulations with the computer aided design software. Testing is not focused on the discovery of errors, only to confirm the accuracy of the design. The starting point is that the tests will show that no changes are necessary. This is used as an important argument why it is no problem to start full production. For example, there are currently 17 aircraft in assembly, including the first four production aircraft of the first Low Rate Initial Production Series. Some may ask, how the theory of testing relates to the words of Tom Burbage, vice president of Lockheed Martin, responsible for the JSF project, last December 2008 at the rollout ceremony of the JSF prototype AF-1, he said: “The AF-1 contains a wide range of evolutionary improvements and updates that have emerged as a result of the test flights with the AA-1 flight test program of the past two years.” So, it looks like testing is more than verifying a checklist, to confirm the accuracy of the computer designs. With only 1% of the test flights hours performed, the question may arise: “What if in the remaining 99% of the test program again and again a series of evolutionary improvements and upgrades is needed. What will be done with the aircraft already produced? And who will pay for that?”

An important question, as the Royal Netherlands Airforce is planning to buy the 16th F-35A production unit to participate in the IOT&E stage of the project in 2013-2014.

Critical question of Dutch Parliament answered incorrectly

On May 8, 2008, after critical questions of the Dutch Parliament about the overlap between test program and production, Deputy Minister of Defence Jack de Vries wrote the Lower House “According to plan, the AA-1 will perform an additional 50 flights until January 2009. The total testing is on schedule.” This has to be considered as not being correct information.
On May 8, 2008, only 40 flights were completed and on January 1, 2009, the AA-1 had performed only 69 flights. Considerably less, however the Lower House is still not informed. In May 2008 the test program was not on track, but 14 months behind schedule. At this moment the testprogram is 18-20 months behind schedule. It will be interesting to see what Jack de Vries will report in April 2009 the Lower House and the public about the progress of the JSF test flight program.

Comments RSS

Reageer ook

Je moet ingelogd zijn om een reactie te kunnen plaatsen.