Author Archives: David Cenciotti

Su-27 Inside Area 51, WC-135 Nuke Sniffer Saga, Iran’s Stealth Jet Update, And Much More: The Aviationist’s Top Stories Of 2017

The five top stories of The Aviationist provide the readers the opportunity to virtually review what happened in 2017.

Ordered by pageviews, the following 5 posts got the most reads and comments among the articles published on The Aviationist this year.

Needless to say, we have covered many more topics during the past year: the mysterious crash of an unidentified aircraft type that cost the life of Col. Eric Schultz; the Syrian Su-22 shot down by a U.S. Navy Super Hornet over Syria; the F-35 Lightning II (first special tail; first female pilot; Israeli IOC; birdstrikes and subsequent theories; etc); the Russian Su-57 (formerly PAK FA); the B-21 Raider; the North Korean crisis; some serious accidents across Europe; and much, much more…

BTW, we have also published an ebook on the A-10 Thunderbolt titled “BRRRTTT…deployments, war chronicles and stories of the last A-10 Warthogs” that is now available in paperback version on Amazon.

Please use the search feature on the site or select the proper category/tag to read all what we have written throughout the last year.

1) These crazy photos show a Russian Su-27 Flanker dogfighting with a U.S. Air Force F-16 inside Area 51

The two jets almost overlap (the Su-27 is farther, the F-16 is closer to the camera), during a dogfight inside Area 51.

Jan. 06 2017

You don’t happen to see a Su-27 Flanker dogfighting with a F-16 unless you visit Area 51. Here are the amazing photographs taken near Groom Lake, on Nov. 8, 2016, U.S. election day.

The photographs in this post were taken from Tikaboo Valley, near Groom Lake, Nevada, by Phil Drake, who was lucky enough to observe a Su-27P Flanker-B dogfighting with an F-16, presumably one of the four Groom Lake based -D models in the skies of the famous Area 51.

Although the quality of the pictures is low (the aircraft were flying between 20K and 30K feet) they are extremely interesting since Flankers operating from Groom are not a secret (they have been documented in 2003 – 2004 and more recently between 2012 and 2014) but have rarely been photographed.

Here’s Phil’s report of the rare sighting:

“The date was November 8th, US election day, and the sighting was between 1500 and 1525.

I was visiting Nevada hoping to catch a glimpse of some of the latest defense programmes being tested.

On the Monday and Wednesday, Nellis Aggressor F-15s and F-16s were regularly overhead, dropping flares and sonic booms.  It was Tuesday afternoon when the skies went quiet for a couple of hours, and I hoped this may be a sign of something unusual being flown.

Eventually the sound of jet noise caught my attention, and I scanned the clear blue skies ’til I saw the tiny speck of an approaching military jet at high altitude, leaving an intermittent contrail.

It was instantly recognisable as a Russian built Sukhoi 27 Flanker, and carried no national insignia or identifying marks.

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2) U.S. Air Force deploys WC-135 nuclear sniffer aircraft to UK as spike of radioactive Iodine levels is detected in Europe

The WC-135 nuke sniffer (Air Force photo by Staff Sgt. Christopher Boitz)

Feb. 19 2017

The USAF WC-135C Constant Phoenix might be investigating a spike in radioactive levels in Norway. Someone speculates the release of this radionuclide could be the effect of a Russian nuclear test.

On Feb. 17, 2017, U.S. Air Force WC-135C Constant Phoenix Nuclear explosion “sniffer,” serial number 62-3582, using radio callsign “Cobra 55” deployed to RAF Mildenhall, UK.

As we have already reported the WC-135 is a derivative of the Boeing C-135 transport and support plane. Two of these aircraft are in service today out of the ten examples operated since 1963. The aircraft are flown by flight crews from the 45th Reconnaissance Squadron from Offutt Air Force Base while mission crews are staffed by Detachment 1 from the Air Force Technical Applications Center.

The WC-135, known as the “sniffer” or “weather bird” by its crews, can carry up to 33 personnel. However, crew compliments are kept to a minimum during mission flights in order to lessen levels of radioactive exposure.

Effluent gasses are gathered by two scoops on the sides of the fuselage, which in turn trap fallout particles on filters. The mission crews have the ability to analyze the fallout residue in real-time, helping to confirm the presence of nuclear fallout and possibly determine the characteristics of the warhead involved.

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3) New Photos And Video of Iran’s Homemade F-313 “Qaher” Stealth Jet Have Just Emerged. And Here’s A First Analysis

The F-313 during taxi tests (highlighted the main differences since the first appearance in 2013).

Apr. 15 2017

A new prototype of the weird Qaher 313 stealth jet has conducted taxi tests.

Footage and photographs showing a new prototype (marked “08”) of the famous Qaher F-313 stealth fighter jet have just emerged as Iran’s President Hassan Rouhani participated Saturday in an exhibition displaying the achievements that the Defense Ministry Brigadier General Hossein Dehqan gained during the past two years.

Indeed, an “upgraded version” of the “faux stealth fighter” can be observed performing taxi tests. The aircraft appears to be slightly different from the one unveiled on Feb. 2, 2013, that was nothing more than a poorly designed mock-up that would never fly unless it was extensively modified and heavily improved.

Four years ago, the cockpit was basic for any modern plane, the air intakes appeared to be too small, the engine section lacked any kind of nozzle meaning that the engine would probably melt the aircraft’s back-end. Above all, the aircraft was way too small to such an extent its cockpit could not fit a normal-sized human being.

The new prototype retains the original weird shape but has a more realistic cockpit, large enough to accommodate an Iranian test pilot on an ejection seat, with a “normal” canopy (the previous one was clearly made of plexiglass), and a dorsal antenna. It is equipped with dual exhaust nozzles: according to some sources these are U.S. engines, according to others these would be new turbofan engines or modified Iranian J-85s. And, interestingly, a sort of FLIR (Forward Looking Infra-Red) turret was attached to the nose of the aircraft, that also features a white radome.

Although the new prototype is not a complete joke as its predecessor, it is still pretty hard to say whether it will be able to take to the air and land safely without further modifications: the intakes continue to appear smaller than normal (as commented back in 2013, they remind those of current drones/unmanned combat aerial vehicles); the wing are small as well and feature the peculiar design with the external section canted downward whose efficiency is not clear.

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4) U.S. Department Of Defense Video Shows Unknown Object Intercepted By U.S. Navy Super Hornet And We Have No Idea What It Was.

ATFLIR footage of a mysterious object intercepted by USN F/A-18 Super Hornet in 2004.

Dec. 12 2017

This video shows the weird object as seen from a U.S. Navy F/A-18F Super Hornet’s ATFLIR (Advanced Targeting Forward Looking Infrared) pod. What is it? Any idea?

On Dec. 16, the NYT published an interesting story about a U.S. Department of Defense program that investigated reports of UFOs (unidentified flying objects). Along with interviews with program participants and records they obtained investigating the mysterious Pentagon program, The New York Times has released a video that shows a close encounter between an F/A-18F Super Hornet out of USS Nimitz and one of these UFOs back in 2004.

Back in 2007, a user (cometa2) of the popular Above Top Secret (ATS) forum posted an alleged official CVW-11 Event Summary of a close encounter occurred on Nov. 14, 2004. Back then, when the encounter had not been confirmed yet, many users questioned the authenticity of both the event log and the footage allegedly filmed during the UFO intercept. More than 10 years later, with an officially released video of the encounter, it’s worth having a look at that unverified event log again: although we can’t say for sure whether it is genuine or not, it is at least “realistic” and provides some interesting details and narrative consistent with the real carrier ops. Moreover, the summary says that the callsign of the aircraft involved in the encounter is Fast Eagle: this callsign is used by the VFA-41 Black Aces – incidentally the very same squadron of David Fravor, formed Co of VFA-41, the pilot who recalled the encounter to NYT.

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5) Rare Photo Shows F-4 Phantom Flying Inverted While Intercepting A Russian Tu-95 Bear Bomber

The famous shot of the inverted flying F-4 Phantom (the aircraft was actually ending a barrel roll).

Dec. 04 2017

“Because I was….inverted!”: Top Gun stunt performed near a Russian strategic bomber.

In the last few years, we have often reported about “unsafe and unprofessional” intercepts conducted across the world by Russian (and Chinese) fighter jets scrambled to identify and escort U.S. spyplanes flying in international airspace.

Barrel rolls, aggressive turns that disturbed the controllability of the “zombie” (intercepted aircraft in fighter pilot’s jargon), inverted flight: if you use the search function on this site you can read of several such incidents that made the news on media all around the world.

The last episode involved a Russian Su-30 that crossed within 50 feet of a U.S. Navy P-8 Poseidon’s path over the Black Sea during an intercept mission, causing the American maritime patrol aircraft to endure violent turbulence, on Nov. 25, 2017.

However, as a former RC-135 aircraft commander who flew the S, U, V, W, and X models, told us a couple of years ago:

“Prior to the end of the Cold War interceptors from a variety of nations managed to get into tight formation with RC-135s and EP-3s. Smaller airplanes like MiG-21s made it easy. The challenge with the larger airplanes like the Su-27 and MiG-31 is the sheer size of the interceptor as it moves in front of any portion of the intercepted plane.

At least the Su-27 pilot has excellent all-around visibility to see where the back-end of his own airplane is as he maneuvers adjacent to the RC-135.

The U-Boat crew took video of the intercept, which has not been released but shows the precise extent of how close the FLANKER really was. Recent movies taken by a PRC aircraft that was intercepted by a JASDF F-15CJ suggests that the Eagle was very close—until the camera zooms out and shows the Eagle was 70-100 feet away from the wingtip….

Finally, although the number of Russian reactions to Western recon flights has been increasing recently, for 15-20 years (certainly from 1992 through 2010) there were almost no reactions on a regular basis. As such, what passes for dangerous and provocative today was ho-hum to recon crews of my generation (although we weren’t shot at like the early fliers from 1950-1960).”

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California ANG’s 144th FW Launched 16 F-15 Eagle Jets In The Wing’s First Ever Large-Scale Aircraft Generation Exercise

California Air National Guard’s “Quick Draw” exercise put the 144th Fighter Wing’s readiness to test.

On Dec. 21, the 144th Fighter Wing, based at California Air National Guard Base Fresno, California, took part in Operation Quick Draw, the wing’s first ever large-scale aircraft generation exercise. During the uncommon drills, the unit, whose mission is to provide Air Superiority in support of worldwide joint operations as well as Air Defense of the West Coast of the United States, was called to prepare as many F-15 Eagles for combat as possible with only a 24-hour notice.

In the end the unit was able to generate and launch 16 out of 16 F-15 Eagle fighter jets, a 100% success rate according to Col. Reed Drake, Commander of the 144th FW.

A 144th FW pilot prepares to launch during Operation Quick Draw.

Although pretty uncommon in the past, these short-notice combat readiness drills are becoming part of the periodic ANG units tactical evaluations: on Nov. 22, more or less one month before the 144th FW executed the Quick Draw, the 142nd Fighter Wing/123rd Fighter Squadron “Redhawks”, based at Portland International Airport, took part in a similar exercise launching 13 F-15s within 24 hours. With ANG units supporting the various iterations of a Theater Security Package (TSP), a temporary deployment from CONUS (Continental US) of a force whose aim is to augment the Air Force presence in a specific region for deterrence purposes, assessing the Fighter Wing’s ability to deploy anywhere in the world with a short notice has become extremely important. And the 144th FW is among the units that have already deployed abroad in support of a TSP as part of an EFS (Experiditionary Fighter Squadron): in April 2016, along with the 104th Fighter Wing, Barnes Air National Guard Base, the 144th Fighter Wing, deployed to Europe with a dozen F-15s (four were deployed to Iceland to provide air policing duties) for a 6-month TSP in support of Operation Atlantic Resolve, with the goal to “[…] demonstrate the U.S. commitment to a Europe that is whole, free, at peace, secure, and prosperous and to deter further Russian aggression.”

The F-15Cs of the 144th FW prepare to launch from Fresno ANGB on Dec. 21, 2017.

Image credit: Air National Guard photo by Senior Master Sgt. Chris Drudge

U.S. Marine Corps Planning F-35B Deployment to CENTCOM Area Of Responsibility To Get “First Taste Of Combat” In 2018

The USMC may have their “baptism of fire” with the F-35B next year.

The F-35B, the STOVL (Short Take Off Vertical Landing) variant of the Lightning II 5th generation aircraft is expected to deploy to the Pacific and Central Command theaters in 2018, the Marine Corps Times reported.

According to Jeff Schogol, the F-35B, that can operate from amphibious assault ships, “is expected to deploy with two Marine expeditionary units to the Pacific and Central Command theaters in the spring and summer. […]  The first deployment will be with the 31st MEU aboard the amphibious assault ship USS Wasp and the second will be with the 13th MEU aboard the amphibious assault ship USS Essex, said spokeswoman Capt. Sarah Burns.”

The first deployment to the U.S. Central Command AOR (area of responsibility) – that includes Iraq, Syria, Iran, Yemen and Afghanistan – has long been anticipated. In 2016, Lt. Gen. Robert Walsh, head of Marine Corps Combat Development Command, told reporters that the service was planning to deploy the F-35B to the CENTCOM area of operations aboard the USS Essex (six more F-35Bs were to deploy to the Pacific aboard the USS Wasp).

The 2018 deployment follows the relocation of Marine Fighter Attack Squadron 121 (VMFA-121), an F-35B squadron with 3rd Marine Aircraft Wing to MCAS Iwakuni, Japan, from MCAS (Marine Corps Air Station) Yuma, Arizona, on Jan. 9, 2017. Since then, the F-35B have started operating in the region, taking part in local drills as well as some routine “shows of force” near the Korean Peninsula: for instance, on Aug. 30, four U.S. Marine Corps F-35B Lightning II joined two USAF B-1B Lancers from Guam onf a 10-hour mission that brought the “package” over waters near Kyushu, Japan, then across the Korean Peninsula. Interestingly, during that mission, the F-35Bs flew with the radar reflectors used to make LO (Low Observable) aircraft clearly visible on radars and also dropped their 1,000-lb GBU-32 JDAMs (Joint Direct Attack Munitions) on Pilsung firing range. On a subsequent mission on Sept. 18, the aircraft took part in a “sequenced bilateral show of force” over the Korean peninsula carrying “live” AIM-120 AMRAAM missiles in the internal weapons bays.

A U.S. Marine Corps F-35B Lightning II aircraft with Marine Fighter Attack Squadron (VMFA) 121 departs Marine Corps Air Station Iwakuni, Japan, Sept. 18, 2017. The F-35B Lightning II aircraft joined United States Air Force, Japan and Republic of Korea Air Force aircraft in a sequenced bilateral show of force over the Korean peninsula. This show-of-force mission demonstrated sequenced bilateral cooperation, which is essential to defending U.S. allies, partners and the U.S. homeland against any regional threat. Note the AIM-120 barely visible inside the weapons bay (U.S. Marine Corps photo by Cpl. Aaron Henson)

As already reported, the F-35s would be probably involved in the Phase 4 of an eventual pre-emptive air strike on Pyongyang, the phase during which tactical assets would be called to hunt road-mobile ballistic missiles and any other artillery target that North Korea could use to launch a retaliatory attack (even a nuclear one) against Seoul.

Moreover, during the opening stages of an air war, the F-35Bs would be able to act as real-time data coordinators able to correlate and disseminate information gathered from their on board sensors to other assets contributing to achieve the “Information Superiority” required to geo-locate the threats and target them effectively.

Considered that Marine aviation officials have said that up to half of the current F/A-18 Hornets are not ready for combat, the deployment to the CENTCOM AOR a key step in the long-term plan to replace the legacy F/A-18 Hornet, EA-6B Prowler, and AV-8B Harrier fleets with a total of 353 F-35Bs and 67 F-35Cs by 2032.

Touchdown imminent during “Proof of Concept” demonstration on the USS America (LHA-6) November 19, 2016. (Todd Miller)

In October 2016, a contingent of 12 F-35Bs took part in Developmental Test III aboard USS America followed by the Lightning Carrier “Proof of Concept” demonstration on the carrier on Nov. 19, 2016. During the POC, the aircraft proved it can operate at-sea, employing a wide array of weapons loadouts with the newest software variant and some of the most experienced F-35B pilots said that “the platform is performing exceptionally.” The eventual participation in a real operation such as Operation Inherent Resolve (OIR) over Syria and Iraq, albeit rather symbolic, will also be the first opportunity  to assess the capabilities of the platform in real combat. As for the Israeli F-35s, the airspace over the Middle East (or Central Asia) could be a test bed for validating the tactical procedures to be used by the new aircraft in the CAS (Close Air Support) mission with added Intelligence, Surveillance & Reconnaissance (ISR) and Command & Control (C2) capability.
If committed to support OIR, the F-35B will probably operate in a “first day of war” configuration carrying weapons internally to maintain low radar cross-section and observability from sensors playing both the “combat battlefield coordinators” role, collecting, managing and distributing intelligence data, and the “kinetic attack platform” role, dropping their ordnance on the targets and passing targeting data to older 4th Gen. aircraft via Link-16. More or less what done by the USMC F-35Bs during Red Flag 17-3 earlier in 2017; but next year it will be for the real thing.

Top image credit: U.S. Marine Corps photo by Lance Cpl. Becky Calhoun

The Blackbird NASA Used For Validating The SR-71 Linear Aerospike Experiment Configuration

The iconic SR-71 was used by NASA to undertake a series of experiments. To carry out some of these testing activities the Blackbird was installed an interesting pod.

According to official records, NASA has operated a fleet of seven Blackbirds:

YF-12A (60-6935) – December 1969 to November 1979
YF-12A (60-6936) – March 1970 to June 1971
SR-71A/YF-12C (61-7951/“06937”) – July 1971 to December 1978
SR-71A (61-7971/NASA 832) – January 1995 to June 1996
SR-71A (61-7967) – August 1995 to January 1996
SR-71B (61-7956/NASA 831) – July 1991 to October 1997
SR-71A (61-7980/NASA 844) – September 1992 to October 1999

The last SR-71 flight was made on Oct. 9, 1999, at the Edwards AFB air show. The aircraft used was NASA 844 that flew to 80,100 feet and Mach 3.21 in the very last flight of any Blackbird. Actually, the aircraft was also scheduled to make a flight the following day, but a fuel leak grounded the aircraft and prevented it from flying again. The NASA SR-71s were then put in flyable storage, where they remained until 2002. Then, they were sent to museums.

Throughout their career at NASA, Blackbirds have served as test beds for a series of high-speed and high-altitude research programs:

“As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas — aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization,” says NASA Dryden’s Blackbird website.

“The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the “peak” overpressures of sonic booms and minimize the startling affect they produce on the ground.”

This close-up, head-on view of NASA’s SR-71A Blackbird in flight shows the aircraft with an experimental test fixture mounted on the back of the airplane. (1999 NASA /Photo Jim Ross)

Among the major experiments flown with the NASA SR-71s, there was a laser air data collection system that used laser light, instead of air pressure measured by pitot tubes and vanes extending into the airstream, to determine airspeed, angle of attack, vertical speed, and other attitude reference data.

Another project involved a Dryden’s SR-71 as a platform to film with an ultraviolet video camera, celestial objects in wavelenghts that are blocked to ground-based astronomers. Moreover, the SR-71 was also a testbed in the development of Motorola’s IRIDIUM commercial satellite-based, instant wireless personal communications network, acting as a surrogate satellite for transmitters and receivers on the ground.

Between 1997 and 1998, one NASA Blackbird was used for the Linear Aerospike Rocket Engine, or LASRE Experiment, whose goal was to provide data to validate the computational predictive tools used to foresee the aerodynamic performance of future single-stage-to-orbit reusable launch vehicles (SSTO RLVs).

SR-71 #844 taking off for a LASRE experiment. (NASA)

As part of the LASRE experiment, the Blackbird completed seven initial research flights from Edwards. The first two flights were used to determine the aerodynamic characteristics of the LASRE apparatus (pod) on the back of the SR-71 whereas five later flights focused on the experiment itself.

The LASRE experiment itself was a 20-percent-scale, half-span model of a lifting body shape (X-33) without the fins. It was rotated 90 degrees and equipped with eight thrust cells of an aerospike engine and was mounted on a housing known as the “canoe,” which contained the gaseous hydrogen, helium, and instrumentation gear. The model, engine, and canoe together were called a “pod.” The experiment focused on determining how a reusable launch vehicle’s engine flume would affect the aerodynamics of its lifting-body shape at specific altitudes and speeds. The interaction of the aerodynamic flow with the engine plume could create drag; design refinements looked at minimizing this interaction. The entire pod was 41 feet in length and weighed 14,300 pounds.

Two test flights were used to cycle gaseous helium and liquid nitrogen through the experiment to check its plumbing system for leaks and to test engine operational characteristics. During the other three flights, liquid oxygen was cycled through the engine. Two engine hot-firings were also completed on the ground. A final hot-fire test flight was canceled because of liquid oxygen leaks in the test apparatus.

The experimental pod was mounted on NASA’s SR-71 #844. Lockheed Martin may use the information gained from the LASRE and X-33 Advanced Technology Demonstrator Projects to develop a potential future reusable launch vehicle.

This is a rear/side view of the Linear Aerospike SR Experiment (LASRE) pod on NASA SR-71, tail number 844. This photo was taken during the fit-check of the pod on Feb. 15, 1996, at Lockheed Martin Skunkworks in Palmdale, California. (NASA)

NASA and Lockheed Martin were partners in the X-33 program through a cooperative agreement but the program was cancelled in 2001.

A rendering of the X-33 concept (NASA)

Throughout its career, the high-altitude SR-71s, involved in test flights as well as operative missions, have probably contributed to fuel UFO (Unidentified Flying Object) conspiracy theories. For instance, according to CIA high-altitude testing of the then new and secret U-2 led to an increase in reports of UFOs:

“According to later estimates from CIA officials who worked on the U-2 project and the OXCART (SR-71, or Blackbird) project, over half of all UFO reports from the late 1950s through the 1960s were accounted for by manned reconnaissance flights (namely the U-2) over the United States. This led the Air Force to make misleading and deceptive statements to the public in order to allay public fears and to protect an extraordinarily sensitive national security project. While perhaps justified, this deception added fuel to the later conspiracy theories and the coverup controversy of the 1970s. The percentage of what the Air Force considered unexplained UFO sightings fell to 5.9 percent in 1955 and to 4 percent in 1956.”

Flash forward to 2017, we can’t but notice that, among the theories surrounding the footage of an unidentified flying object (UFO) filmed by an F/A-18F Super Hornet in 2004, there is also the one that the weird “capsule-shaped” object might have been some sort of secret aerial vehicle during a test mission rather than an alien spacecraft…. And it would not be the first time.

Here’s Boeing Submission To The U.S. Navy MQ-25 Stingray Unmanned Carrier Aviation Air System Competition

Boeing’s MQ-25 unmanned aircraft system has been unveiled.

After teasing its shape with a mysterious tweet that included a photograph of an aircraft under protective cover on Dec. 14, as planned, Boeing has unveiled a better (still, partial) view of its submission to the MQ-25 Stingray unmanned carrier aviation air system competition (UCAAS).

Through its MQ-25 competition (with final proposals due on Jan. 3, 2018), the U.S. Navy plans to procure unmanned refueling capabilities that would extend the combat range of deployed Boeing F/A-18 Super Hornet, Boeing EA-18G Growler, and Lockheed Martin F-35C fighters. The UCAAS will operate from both land bases and the flight deck of its Nimitz- and future Ford-class aircraft carriers, seamlessly integrating with a carrier’s catapult and launch and recovery systems. The induction of the new tanker drone will offload some aerial refueling duties from the F/A-18E/F Super Hornet fleet.

“Boeing has been delivering carrier aircraft to the Navy for almost 90 years,” said Don ‘BD’ Gaddis, a retired admiral who leads the refueling system program for Boeing’s Phantom Works technology organization, in a company public release. “Our expertise gives us confidence in our approach. We will be ready for flight testing when the engineering and manufacturing development contract is awarded.”

According to Boeing the UAS (Unmanned Aerial System) is completing engine runs before heading to the flight ramp for deck handling demonstrations early next year.

The Navy issued its final request for proposals in October. Proposals are due Jan. 3.

With Northrop Grumman withdrawing from the competition in October 2017, Boeing, General Atomics, and Lockheed Martin are the three aerospace company competing for the initial development contract. The U.S. Navy has a requirement for 72 tanker drones, even though the service will initially only buy four examples of the winning design in order to assess whether the winner will be able to meet all the requirements before handing out any larger production deals.

Top image: Boeing photo by Eric Shindelbower