Software Development + Helmet & Other Issues for F-35

Schwartz: Software may slow F-35 development By Dave Majumdar - Sunday Mar 6, 2011


"The painstaking effort to write the complex software for the F-35 may slow development of the fighter jet, the Air Force’s top uniformed officer said.

Air Force Chief of Staff Gen. Norton Schwartz said his service’s version of the tri-service stealth fighter is showing “good software stability,” but also that he was worried that the Joint Strike Fighter program might not be able to finish and test the software on time.

That might cause the software to become “the pacing item in terms of the development schedule,” Schwartz said last week at a conference hosted by Credit Suisse.

JSF program officials don’t dispute that, but say they have added extra time and more software engineers to stave off delays.

“The schedule and resourcing has been adjusted to address the risks that we saw associated with those next steps,” Maj. Gen. C.D. Moore, deputy JSF program manager, said at the same conference.

The F-35 program has been producing software at a world-class rate, but bringing the various bits of software together and integrating it with other onboard systems has historically been problematic, Moore said.

Along with software, Schwartz said, the plane’s production schedule and technical glitches with the helmet-mounted display were his top concerns about the F-35A.

He also said the fighter was structurally sound but has a few aerodynamic “hot spots.” The aircraft continues to perform well in flight tests, exceeding both its planned time aloft and test points.

“From a performance point of view the platform looks solid, but there a couple other aspects that are worrisome,” he said.

Schwartz also questioned whether Lockheed Martin would be able to deliver aircraft as scheduled.

“The more fundamental issue is the ability of the factory floor to produce machines on time and with minimum change work and so forth,” he said. “I’ve been disappointed in the fact that the schedule has continued to slip. We had a plan for nose-to-tail exchange between legacy aircraft and the F-35. That plan has been upset. … It’s a pain in the a$$.”

He implored Lockheed Martin to “deliver what they promised.”

The JSF program office said that the program is keeping to its revised schedule.

“The production line, right now, is holding schedule. I think that’s the first time I can stand in front of you and say that,” Moore said.

Right now, there are 100 aircraft in some stage of the manufacturing process, and 50 should be flying by 2012, he said.

Moore said that he expects the process to improve and get cheaper as experience builds. Production should start to increase in 2013.

But Moore said Congress’ inability to pass a 2011 budget has held up negotiations over low rate initial production lot 5.

“Until Congress speaks and gives us that direction, our LRIP 5 negotiations will be somewhat delayed,” Moore said.

He said he expects the number of aircraft to be “in the 30 range,” but said that would likely require “some level of relief” — more money than allowed under the prevailing continuing resolution.

Helmet-mounted display
Schwartz also noted problems with the helmet’s visor, which is meant to display various flight data and even night-vision images captured by fuselage-mounted cameras.

“The helmet-mounted display has some issues which will need to be addressed, clearly, particularly with an airplane without a head-up display,” he said.

Moore said program officials are looking at alternative displays in hopes of using competition to spur contractors into correcting the problems.

Drew Brugal, president of Vision Systems International, which makes the F-35 helmet, said he was not surprised by the generals’ comments.

“I also suspect that comments about VSI being a concern will not abate until there is a schedule in place, and we have had more flight and positive comments on the ECP-1 [helmet mounted display] configuration,” Brugal said.

But he said his team and Lockheed were working on solutions. VSI plans to add a better magnetic head-tracker and a higher-resolution display, fixes meant to solve problems with jittery images and poor readability, and anticipated problems with night vision.

“We are still working with LM to define an executable schedule that demonstrates a low level of risk in [Lockheed Martin’s] eyes. The team is in Fort Worth right now working on this,” Brugal said. “I anticipate that once there is a meeting of the minds between [Lockheed Martin] and VSI, the program office will be briefed.”

He predicted that criticism would dissipate after the company’s plan is presented to the F-35 program office."

Source: http://www.airforcetimes.com/news/2011/ ... t-030611w/

discofishing wrote:... I think the helmet issue is minor, I'm not worried about it.... I imagine designing things right the first time, based on lessons learned in the past, will end up saving money in the long run. My two cents worth...

discofishing wrote:What are these few aerodynamic hot spots they're talking about?

Lockheed rolls out JSF for stealth tests June 16, 2009

"US aerospace firm Lockheed has rolled out a special F-35 Lightning Joint Strike Fighter (JSF) aircraft for full tests of its radar evading capabilities.

Lockheed said the aircraft came out of the factory in Fort Worth, Texas fully equipped with the full range of stealth capabilities that are designed to make it invisible to hostile radars.

The aircraft will be used to assess whether the F-35 is as stealthy as intended....

...Lockheed JSF program manager Dan Crowley said the rollout of the stealth test aircraft was in line with a test schedule commitment made two years ago....

...Lockheed vice-president of F-35 development J.D. McFarlan said the test aircraft - termed a Highly Accurate Low Observable (HALO) radar pole model - would be used in tests to provide data about the radar-signature characteristics of the F-35 aircraft family.

He said initial testing would be conducted in a special radio test facility in Fort Worth, with follow-on tests at a remote site.

"At the remote site, the model will be affixed to a tall pole and tested in the open air, hence the term pole model," he said."

Source: http://www.lowcountrynet.org/sc-economi ... ealth.html

JANICKI INDUSTRIES' PROTOTYPE EXPERTISE TAPPED FOR F-35 PROGRAM

"June 16, 2010 Sedro-Woolley, WA – Janicki Industries' expertise in building composite prototypes was tapped by Lockheed Martin in producing the Full Scale Pole Model for its F-35 stealth fighter jet program. The model is now being used to test radar signature and other key performance data. High fidelity Radar Cross Section (RCS) testing of HALO has validated the accuracy of the predicted F-35 stealth signature performance over a broad elevation and frequency range.

The center-body innovation
Janicki Industries worked as a key partner with Lockheed Martin throughout the development and fabrication of the Highly Accurate Low Observable (HALO) pole model, beginning in 2006. The demanding timeline for F-35 development drove several innovations during the project, including building a structural inner body in advance of final surface engineering. By building the center-body concurrently with the aircraft engineering phase, the Janicki/Lockheed Martin team was able to start building the model more than a year in advance of receiving the final surface geometry.

Creating the model body
Once the external shape of the model was established, Janicki Industries applied a surface to the center-body using a proprietary technology developed by its tooling engineers. This began by applying spray-able, expanding urethane foam to act as a foundation. The foam was machined, then covered with a unique material developed by Janicki specifically for the project. To address the entire surface of the model's body in just two set-ups, Janicki's largest machining center was used. The company's custom 5-axis CNC machining centers are among the largest in the world, with envelopes up to 100 ft x 20 ft x 8 ft.

Producing the external panels
After completing the model's body, the Janicki team began developing and producing composite external panels for the pole model. These panels were fastened to the finished body to replicate the F-35 aircraft for testing purposes. These panels required the strictest adherence to every design aspect so that the model would match the aircraft's real production specifications. Janicki Industries produced highly accurate molds to fabricate the composite panels. After panel fabrication, Janicki converted the molds to specialized trim and drill fixtures, which resulted in significant cost savings for the F-35 project.

Assembling the pole model
During testing, the Highly Accurate Low Observable model is rigged in a variety of orientations on the top of a test pole. The model is uniquely configured for either upright or inverted orientation on the pole. This requires it to be re-configurable both structurally and cosmetically to accurately represent the air-frame in either orientation.

Rather than addressing all pole model assembly tasks at Lockheed Martin's facilities as originally planned, the company tapped Janicki Industries' extensive fabrication capabilities, entrusting the Janicki team to assemble major portions the final model. Janicki completed multiple technically-complex assemblies including wings, engine mounts, internal structure and inlet duct assembly."

http://www.janicki.com/images/stories/n ... 5.halo.jpg
Source: http://www.janicki.com/f-35-halo-pole-m ... or-testing

popcorn wrote:Not that I'm complaining but I've noticed that there's never been any mention of problems/shortcomings related to the jet's stealthiness? Has any testing been done to determine how the JSF stacks up vs this requirement?

SpudmanWP wrote:It's an A model (see the gun bulge on the upper-right surface (lower-left in the photo).

I haven't a clue as to what those bulges are.