5 Problems with the F-35 Sensors & Avionics

Sensors and avionics are words that fail to express the size and complexity of the systems they describe. In this post I will be examining 5 problems associated with the F-35 sensors & avionics to decide what if any risk they pose to the F-35 Program.

Problem 1 – The AESA Radar’s Electronic Warfare (EW) sensors are not good enough.

“According to Boeing.”

Manufactured by Northrup Grumman the AN/APG81 AESA Radar is designed to enable F-35 pilots to effectively engage air and ground targets at long-range and in all-weather conditions. The radar has built-in electronic warfare capabilities that can emit frequencies to jam radio frequencies, create false targets, attack computer networks, confuse and disable advanced anti-aircraft systems.

These capabilities together with low observability will replace the need for specialist EW support aircraft such as the EC-130H Compass Call, the Boeing EA-18 Growler, Northrop Grumman EA-6B Prowler, F-16CJ Fighting Falcon and the EF-111 Raven (already retired by the US Air Force).

The problem  is based on a claim by Boeing that its’ EA-18G Growler is needed to supplement the F-35 in airspace where there is a high threat from modern surface-to-air missile systems. The claim has gained some legs in the media as the US Navy has included the need for more Growlers in its budget wish list and the support provided by senior US Navy officials. As an example, in a March 2015 Airforce Technology article in quoted Rear Admiral Michael Manazir.

“the [Boeing EA-18G Growler] emits more jamming frequencies than the F-35, making it a much more capable EW platform. A more realistic operational scenario would be for the Growler to support F-35 missions in a complementary role”.

Boeing and the US Navy wanting more Growlers should not automatically be interpreted as the F-35 EW capability being sub-standard. The lobbying can be seen in another context by considering the following points.

Reasons to be a Little Skeptical

  • Boeing needs more orders of any of the current F-18 variants to keep the production line open beyond 2016. Lobbying the powers that be for more Growlers is Boeing’s best chance for more orders.
  • The Navy is skeptical of the F-35 capabilities. Keeping the F-18 production line open provides the security blanket for the Navy if the F-35 were to flop.
  • Boeing’s claim is made without all the facts as most of the F-35 EW capabilities remain classified.
  • Including more Growler’s in the US Navy procurement wish list is a token offer at best. If the Growlers were so important to the Navy, why wouldn’t they secure funds in a real approved budget and buy them?
  • The 513th Electronic Warfare Squadron stood up in 2010 at Eglin Air Force Base. The 513th mission is to enable 5th Generation EW dominance by developing, testing, and fielding prompt and accurate combat capable mission data. The Squadron is staffed by the Air Force, Navy, Marine Corps, and foreign partners buying the F-35. Source: Eglin Air force Base – 53rd Wing Fact Sheet.  

In considering the above information, Boeing and the US Navy seem to be taking advantage of the F-35’s poor reputation to push their agenda. Is this a real problem? – not today. Let’s move on.

Problem 2 The Electro-Optical Targeting System (EOTS) is already Out of Date.

EOTS, is an infra-red sensor that helps pilots with air and ground targeting beyond visual range. Located on the underside of the F-35’s nose behind what looks like a glass housing, its capabilities include day/night passive sensors that cannot be detected by enemy warning systems (Low observability) and high-resolution infrared imagery of a target that was initially detected by the AESA Radar.

There are no technical issues with the current EOTS but Problem 2 is an accurate statement. When designing the F-35, the EOTS was the most advanced specification imaginable. Today, due to extensive delays in development and production ,the targeting technology available to legacy aircraft (e.g. F-16, F-18) now exceeds that of the F-35.

There are two targeting systems used by legacy aircraft today:

  • Lockheed Martin’s “Sniper” Targeting System; and
  • Northrop Grumman LITENING Targeting System.

Both have advanced capabilities in areas that did not exist when designing the F-35. It is in Close Air Support (CAS) that the outdated EOTS technology is of most concern. The current EOTS is missing both an infrared pointer and live video streaming to troops on the ground. Both capabilities are now mandatory for any sorties conducted in the middle east area. Without these systems were does this leave the F-35?

EOTS does not include an  Infrared Pointer

A pilot can use the infrared pointer to alert the Ground Controller that troops are in their vicinity. The Ground Controller can then use their equipment to confirm if they are a friend or foe. Alternatively, when ground troops pass target coordinates to the pilot, that pilot can turn on the infrared pointer to highlight the intended target and ask the Ground Controller to confirm the correct target is illuminated.

The F-35 doesn’t offer live Video Streaming to Ground Troops

The current Sniper and Litening targeting systems are able to stream full-motion and high quality live video feeds of the area to ground troops. The F-35 has a couple of problems in this area:

  • The F-35’s EOTS camera does not have the range or high-resolution capability needed by the ground troops for the video link to be effective.
  • The software used with the F-35 today is not capable of transmitting video. A future avionics software upgrade will offer this capability. As is so often the case, the ground troops will need to be patient as the upgrade is not due until 2019 at the earliest. This is an avionics problem not an EOTS limitation.

Lockheed Martin has a Solution for Problem 2:

It announced in September 2015 that it had developed “Advanced EOTS” that can be incorporated into the F-35 during the Block 4 software upgrade (2019-2025). Advanced EOTS incorporates a range of upgrades including the needed infrared marker and improved image detector resolution.

“Advanced EOTS” creates a new problem. As it is not part of the current F-35 requirements “Advanced EOTS” becomes an optional upgrade. In other words it is another cost to be added to the bill for the F-35 Program – hence the problem. The importance of the new targeting system will make sure the system is purchased. It remains to be seen whether the funds to pay for it will be new or provided from cuts made in other areas of the program such as less F-35’s?

Problem 3 – The F-35 Pilots Helmet is too complex and way over priced.

It is hard to argue with this one as the cost of the helmet is $400,000+ each and there has been many technical issues with its performance.

The F-35 Helmet is the heart of all the sensors and avionics in the F-35. If it fails to work as specified there will be a large shadow cast over the F-35 Program.

The Helmet is designed to give pilots a 360 degree situational awareness in any kind of weather, day or night. In a way it provides the pilot with Superman’s X-Ray vision. When the pilot looks down, he doesn’t see his knees—he sees “through” the aircraft, and knows what’s below him” Source: Wired – Phil Jasper, Executive Vice President of Government Systems at Rockwell Collins.

The unprecedented situational awareness is made possible by the Distributed Aperture System (DAS) manufactured by Northrup Grumman.

DAS is a series of six electro-optical sensors (cameras) embedded around the F-35 to keep up its low observability. The cameras and associated sensors, collect and classify data that creates the 360 degree view in the pilot’s Helmet Mounted Display (HMD). The information provided by DAS sensors include:

  • missile approach warnings;
  • countermeasures deployment
  • passive air-to-air radar,
  • off-axis targeting for air-to-air missiles – pilot can assign a display of interest to the HMD, point his/her head to the intended target, designate and shoot
  • wide field-of-view day/night pilot vision.

To date there have been three Helmet Prototypes produced by Rockwell Collins

The Generation 1 (Gen1) Helmet encountered many problems:

  • the display was jittery when the F-35 hit turbulence or took evasive actions.
  • there was a latency in the video which caused pilots to experience motion sickness.
  • the night vision technology didn’t work as well as it should have.
  • a “green glow” obscured the pilots view.
  • the data fusion in the heads-up display did not show all needed data.

The Generation 2 (Gen2) Helmet has less capability than Gen1. This was a conscious decision to make sure a working helmet was available for the Marines to declare IOC. Over 200 Gen2 Helmets are in use today.

The Generation 3 (Gen3) Helmet delivered in August 2015 includes a number of fixes and upgrades. The new Gen3 Helmet will be introduced in 2016 and hopefully prove successful. The capabilities include:

  • fully functioning display of the data provided by the F-35’s DAS sensors.
  • an improved night vision camera.
  • improved visual sharpness.
  • improved liquid-crystal displays.
  • automated alignment and software improvements.

Problem 3’s solution is the Gen3 Helmet – if it works. We should find out in 2016.

Problem 3a – The Helmet is too Heavy

Pilots weighing 136 pounds or lighter have been grounded due to the risk of injury during an emergency ejection.

The announcement was made following a round of Ejection Seat tests. The problem occurs when a pilot weighing 136 pounds or less and was wearing a Helmet weighing 4.8 pounds or more. This combination would create neck loads that exceed what is considered perfectly safe. For the record The Gen3 Helmet weighs 5.4 pounds.

A USA Today article published on 26 October 2015 reports that  Lt. Gen. Christopher Bogdan told a House Armed Services panel that his Office is now trying to shave about 6 ounces from the Helmet to minimise this risk. A revised helmet is expected to be available in 12 to 18 months time.

Problem 3a has a solution. As with Problem 3, we now need to wait for the next iteration.

Problem 4: Communication between Fourth & Fifth Generation Fighters is visable to radar. 

The F-35 Communication, Navigation and Information (CNI) suite of sensors and avionics is manufactured by Northrup Grumman. The CNI allows multiple fighters to be networked and share key data such as targets. There are two modes of communication:

  • The new Multifunction Advanced Data Link (MADL) system that allows data sharing between F-35’s on the same mission; and
  • The Link-16 communication system to allow the F-35 to share data with legacy fighters.

The main difference between these two systems is that the data transmitted via MADL is undetectable to radar allowing the F-35 to stay stealthy, while Link-16 transmissions are detectable.

At present the F-35 can only communicate with legacy aircraft and the F-22 via Link-16. Therefore, if a mission is flown with a mix of 4th and 5th generation fighters, shared data will be visible to radar and location of the stealth aircraft identified.

This fact becomes a problem when the planned number of F-35 starts to be cut back. With less F-35 fighters the likelihood of legacy aircraft remaining in service and participating in missions with the F-35 is growing by the day. The F-35 Program Office identified this problem and initiated a project to find a solution.

The Defence Advanced Research Project Agency (DARPA) has awarded contracts to develop these systems to help with rapid integration and testing. Under those contracts, Boeing, General Dynamics, Lockheed Martin and Northrop Grumman are developing and analyzing promising systems. Examples developed to date include:

  • Lockheed Martin

Lockheed Martin formed an industry team that included Rockwell Collins and L-3 Communications under the banner of Project Missouri – The project has demonstrated a data-linking capability utilising a new waveform developed by L-3 Communications called “Chameleon”. This system provides low-probability of intercept/low-probability of detection transmissions (LPI/LPD) between the F-22 and F-35 to make sure they stay stealthy. Source: Amy Butler Aviation week 

  • Boeing Corporationsensors

Project Talon Hate.  Boeing has developed a system called Talon Hate for the USAF. It is a Pod based system that can be fixed to legacy aircraft allowing secure and undetectable data transmissions between 4th and 5th generation fighters. Using the pod, a mixed flight of F-15s and F-22s could work together, scanning and communicating discreetly to keep the stealth qualities of the F-22. Source War is Boring

Boeing also has a plan to extend the life of the F-15C

In addition to providing a stealthy data link, Boeing is preparing a proposal known as “2040C”. With the necessary upgrades to the F-15, including Talon Hate, Boeing wants to double the missiles the F-15 can carry and become an airborne missile truck for the F-22.  The idea is that F-22’s would lead mixed flights, with the faster stealth fighters with the superior passive sensors finding the targets. The target information will be transmitted via Talon Hate to the F-15 that will be loitering in big numbers and carrying up to 16 missiles each. Source: War is Boring

  • Northrup Grumman

Has demonstrated its data linking capability using its Freedom 550(TM) gateway radio terminal. The terminal Sensorswas successful in transmitting data between 4th (F-18) and 5th generation (F-22) fighters. A benefit of the Northrup Grumman data link is that existing platforms (Link-16, MADL) do not need change.

A solution to Problem 4 is well advanced with testing already conducted on several options.  The problem remains that a decision on implementation of any system has not been made, its cost to the F-35 Program is unknown as is a time for implementation. One thing for sure –  a secure and undetectable transmission of data is not available to the Marines F-35B today or the USAF F-35A when it declares IOC in 2016.

Problem 5:  Undetectable Transmissions can only be shared between a pair of F-35’s. 

The Marines require targeting data to be instantly shared between four F-35B’s to make sure the limited number of weapons are used effectively. The current software associated with the sensors has a bug restricting undetectable transmission to two F-35’s only. This can be best explained by Lt. Gen. Jon Davis, the Marine Service’s Deputy Commandant for Aviation:

“There’s no latency at all with the first two airplanes; there’s no latency problems with ships three and four,” he said. “It’s when I try to tie all four together that sometimes a target is kind of slightly misplaced on the ground, or it’s not but I’m not confident in 100 percent of the cases exactly where it’s supposed to be. As a temporary work around, Lockheed engineers devised a software patch that will share sensors data from two aircraft with another pair of aircraft by using a Link-16 tactical data connection” Source: DefenceTech (

In an ominous representation of the size of Problem 5 to the Marines, the F-35 Program Office has demanded that Lockheed Martin find a permanent solution to this problem for implementation with Software Block 3F in 2017. Lockheed Martin are looking into it.

Report Card

With a greater understanding of the problems faced by the F-35 advanced sensors & avionics, I have provided my subjective four pillars rating below.

My Four Pillars Rating = 57.5%F-35 Program

(With concurrency and Software Blocks in mind, I suggest 50% is a pass, 75% & above is excellent)

Affordability – 2.5/5

  • The Good – Lower costs via less maintenance, improved reliability and EW specific aircraft no longer required.
  • The Bad – the Helmet costs $400,000 each and it is still in development, EOTS needs to be upgraded and a new 5th to 4th generation data link is needed.

Lethality – 2/5

  • The Good – Promises to be good with sensor fusion and situation awareness to give a deadly combination.
  • The Bad – Sensor Fusion is not displaying information accurately, the helmet is yet to prove itself, EOTS is yesterday’s technology. 

Survivability -2/5

  • The Good – Advanced Radar and DAS sensors give excellent early warning of threats, DAS provides timely analysed data to the pilot for fast and correct decisions in attack or defense.
  • The Bad – ground troops lose the ability to receive real-time video links, Link-16 communications are detectable, Helmet has not proven itself.

Supportability – 5/5

  • The Good –  Simplifies maintenance processes, improved reliability and longevity of components, highly configurable equipment, Open Mission Systems being utilised. 
  • The Bad –  None I can find so far.

The Last Word

  • The problems do create risk to affordability, survivability and lethality.
  • Solutions exist to resolve most of the problems identified.
  • Implementation of these Solutions are several years away

My rating for the F-35 sensors and avionics is barely a pass. Is this good enough at this stage of the development of the F-35?

Do you trust the F-35 Program to deliver the solutions in 2-5 years? 

Your thoughts could start a great discussion. 


2 thoughts on “5 Problems with the F-35 Sensors & Avionics

  1. MADL and Link16 datalinks are generally not detectable by radar. Radar is primarily used to detect physical objects, however advanced AESA radars can be used in EW procedures, which may include passive reception and active jamming of certain signals and frequencies. Link16 is powerful and omnidirectional, thus can be detected by a properly configured receiver at significant ranges. MADL is directional and relatively low power, thus the receiver needs to be on the correct azimuth and fairly close to detect or intercept a signal.

    • Thanks for the comment.
      I must admit it was difficult putting this post together. The more I read the more I discovered. Your info is greatly appreciated.

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