Tag Archives: Northrop Grumman

The Incredible B-2 Wing Flutter Video and What It Means.

Test Video Shows Interesting Structural Capabilities of Advanced Aircraft Like B-2.

This remarkable video of a Northrop Grumman B-2 Spirit stealth bomber undergoing wing flutter testing on June 14, 1995 is fascinating for a number of reasons.

All aircraft wings have a remarkable capacity for flex. But one of the most significant changes in aircraft engineering in the last three decades has been the addition of composite materials, especially carbon fibers, into aircraft structural design. In many cases these composite materials have replaced metal alloys in structural components on advanced aircraft.

The B-2 Spirit is approximately 80% composite, mostly carbon fiber. Some of the structural framework internal to the B-2, especially where the wing blends into the fuselage and the largest fuel tanks are located, is titanium and aluminum. While part of the reason for this is structural, another reason is that composites, being made up of a number of different elements, can have radar absorbent materials included in their manufacture or “lay-up” during the process of combining materials into a composite.

There are many reasons composite materials, or materials made up of a combination of advanced materials including metals, polymers (plastics) and carbon atoms at the most elemental level, have become so common in aviation engineering.

Two of the chief reasons are illustrated in this video.

Composites Are Anisotropic.

Anisotropic materials can be engineered to transmit energy differently in different directions. Metals, including metal alloys like aluminum made from the ore bauxite, are isotropic, they only transmit energy in one direction. That means a composite like carbon fiber, being anisotropic, can be engineered to be stiff along one axis or direction of stress, but flexible in another. In the case of this B-2 video, the carbon-fiber composite material in the wings is engineered to absorb energy from aerodynamic stress and bend significantly in the vertical axis, with little change in flight attitude during the flexing. The wings do not twist or begin a similar leading edge to trailing edge vibration, which would change the aircraft’s angle of attack.

Structural elements of a B-2 Spirit. (Photo: Northrop Grumman)

Composites Have Different Fatigue Characteristics.

Eventually all materials fail. The number of normal fatigue cycles a material can endure prior to failure is part of its fatigue limit. In general, isotropic materials like metals and metal alloys have a shorter, lower fatigue limit or number of fatigue cycles. Composite materials like carbon fiber can be engineered at the molecular level to have much longer fatigue limits, enduring more fatigue cycles. And when they reach their fatigue limits, composites tend to fail differently than metals, with cracks propagating through the laminated material very differently than through the often more linear grain structure of a metal or metal alloy. As a result, carbon fiber structures in aircraft can be more durable than alloy structures, one of the reasons for the growing use of carbon fiber composites in advanced aircraft like the B-2 and in future aircraft like the B-21 Raider.

B-2s also have a system called the Gust Load Alleviation System that looks like the aircraft’s beaver tail. The GLAS counters the rolling impact or resonance to smooth out the ride of the B-2 in turbulent conditions and extend the aircraft’s fatigue life. The GLAS also smooths the ride of the B-2 in low altitude flight, even though the B-2 is predominantly designed for the high-altitude flight regime.

Air Force test data from tests like the one in this video and through finite elemental analysis (FEA) modeling suggest the B-2 will remain structurally sound to approximately 40,000 flight hours. This analysis also revealed that the rudder attachment points at the B-2’s wingtips are the highest structural stress areas and will be the first to fail. B-2 Spirits have not implemented an Aircraft Structural Improvement Program (ASIP) as we have seen on the primarily alloy B-52 heavy bombers. Some sources suggest this may make it more difficult to predict an economic service life and attrition rate according to author Don Greer. Given the current engineering limitations established in tests like these, the current B-2 Spirit force will fall below its requirement of 19 aircraft (of which less are combat capable) by the year 2027, making the new B-21 Raider even more important.

A graphic showing the wing loading and stress vectors on a B-2 wing. (Photo: Northrop Grumman)

We Ran a Simulated ICBM Attack on the United States to Find Out: Could We Stop One?

We Went Inside Northrop Grumman Demonstration of Critical Anti-Ballistic Missile Technology.

Sometime in the future, diplomacy may fail.

An overnight incident in the Pacific between a U.S. Navy vessel and an adversary nation submarine causes a collision. A U.S. Air Force surveillance plane is fired upon as it flies near an international airspace boundary. A rogue nation continues ballistic missile testing.

What happens when it becomes a real world crisis with an ICBM (Intercontinental Ballistic Missile)?

A missile launch indication from U.S. Air Force Space Command surveillance satellites happens at 0234 Hrs local. It is 1734 GMT, 10:34 AM in San Francisco, California in the United States. Sunday morning.

Silent lighted icons flash red on a U.S. early warning display. Red circles appear around them. They are automatically given a series of numerical designations: speed, altitude. Sea based radars add to the intelligence picture. More data becomes available. Algorithms extrapolate trajectory, acceleration, apogee, reentry and deceleration into the atmosphere. They calculate the missile’s potential impact point.

Missile launch (credit: Northrop Grumman)

I sit in a chair watching the arc of the incoming ICBM headed to the United States’ west coast. The missile reaches its apogee, its maximum altitude in near space, and begins its terminal attack phase. It happens fast. I realize I am sweating. This feels very real. As real as today’s headlines. As the missile descends toward its target it begins to slow, but it is still moving faster than a rifle bullet.

The United States homeland is under attack by ICBMs launched from a rogue nation. It is the first time a nation state has attacked the U.S. homeland since WWII. A shooting war has started.

Intelligence analysts know the threat of real damage is moderate, but that doesn’t help. The warhead is likely small, crude by modern standards. It may not even function. The guidance system is not very precise. Chances are just as good that this warhead will land short in the Pacific or go long into the California mountains as it will detonate over the intersection of Market Street and 6th Street in the Financial District of San Francisco. It could spread radioactive material over several city blocks depending on the altitude it detonates at. It may even fail to detonate.

But that is not the point of this attack. The point is for a rogue nation to send a clear signal to the U.S. government: We can reach you. We have the will to attack. You are not safe.

Given recent headlines the ballistic missile threat to the United States is in the spotlight. What is the U.S. doing to counter the intercontinental ballistic missile threat?

Recently The Aviationist visited a secure facility at Northrop Grumman to learn more about the present and future of ballistic missile defense for the continental United States. We participated in a chilling drill to intercept an ICBM fired from somewhere on the Asian continent (Editor’s note: at the request of Northrop Grumman officials, we agreed not to name any potential adversary nation specifically).

Inside Northrop Grumman’s facility. (credit: The Aviationist.)

Northrop Grumman’s Ken Todorov, Director of Global Air and Missile Defense, told TheAviationist.com, “This literally is rocket science.”

Todorov directed us through a simulated ICBM intercept over the northern Pacific using Northrop Grumman’s technology contributions to our nation’s Ballistic Missile Defense Systems. Several new technologies are showcased within Northrop Grumman’s Ground-based Midcourse Defense (GMD) system. These systems are not yet operational, but they are must-haves for the nation’s ICBM defense. Given the threat from rogue nations in the Pacific region, Northrop Grumman’s new technologies are not just critical, but essential to our nation’s defense in the immediate term.

Without systems like GMD our west coast is, for the first time in history, under threat of nuclear attack from an ICBM in control of a rogue nation.

A constant stream of data from a wide array of sensors tracks the incoming ICBM. We see the track on our large monitor, nearly the width of the room, and on our individual monitors. It’s eerily quiet.

View to a kill: We run a simulation of an ICBM attack on the U.S. west Coast. (credit: TheAviationist.)

“Ground Based Interceptor launch, Ft. Greely, Alaska.” The systems operator tells us. The track of an ascending missile appears on our screen. It arcs upward gaining momentum, curving to match the downward trajectory of the incoming ICBM.

“Ground Based Interceptor launch, Vandenberg Air Force Base, California.” A second lighted trajectory traces across the screen, originating from the continental U.S. west coast. Two U.S. missiles are in the air, with new proposed Northrop Grumman technology melding the intercept data and targeting information to help provide mid-course intercept data.

The lines converge silently toward one another, beginning to form a brightly lighted “Y” shape on the displays. We all follow the lighted display across the screen, the ICBM arcing downward, the interceptors arcing to meet them.

“This is a bullet hitting a bullet in the exo-atmosphere” Todorov tells us, gesturing to the three missile tracks as they converge together on the big screen. The projectile we are trying to hit is moving at 10,000 MPH now, and it is about the size of a trashcan.

There are four phases of ICBM flight.

The boost phase is the most difficult to intercept the vehicle in, but is where the launch is detected. The ascent phase is vulnerable to detection by the Aegis weapons system and interception by RIM-156 and RIM-174 Standard Missiles launched from land or at sea from U.S. Navy surface ships like the Ticonderoga class cruisers and Arleigh-Burke class destroyers. In the third phase, the “mid-course” phase, the incoming ICBM could be targeted by the exo-atmospheric THAAD missile system or additional systems still in development.

Northrop Grumman technology has the capability to make all these systems perform better together, and improve the likelihood of intercepting missiles before they reach the United States or any user nation.

The lines on the big display in front of us converge.

They complete the big “Y” shape over the eastern Pacific off the California coast. There is no sound. In an instant all three missile designators disappear. The intercept was successful.

Missile tracking system close-up during ICBM launch simulation (credit: The Aviationist)

Using several new key technologies from Northrop Grumman we killed the incoming ICBM over the pacific before it reached the United States.

Later we see video of a successful, actual test intercept of an ICBM target during a demonstration of the Ground-based Midcourse Defense (GMD) element of the ballistic missile defense system on May 30, 2017. A ground-based interceptor was launched from Vandenberg Air Force Base in California. The “anti-missile” missile was armed with an exo-atmospheric kill vehicle projectile. It successfully intercepted and destroyed a simulated ICBM launched from Kwajalein Atoll in the Pacific with a direct collision at re-entry speed and high altitude. The demonstration was widely regarded as impressive proof of the capabilities of the ballistic missile defense system.

Northrop Grumman’s contribution to missile defense is significant. At the beginning of 2017 Ken Todorov told media that, “Members of Congress face a myriad of difficult questions about how to best protect our homeland from a growing number of threats. In this era of declining budgets, it is critical our top national priorities provide those at the “tip of the spear” with the tools to protect our homeland from existing and emerging threats.”

The headlines confirm the ICBM threat from the Pacific region is real, making the need for missile defense perhaps the most urgent defense agenda for the United States.

Note: The Aviationist.com wishes to thank Lauren A. Green, Manager, Branding and External Communications for Northrop Grumman Mission Systems and the entire team at Northrop Grumman for their kind assistance with this article.

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Take a look at these fantastic photographs of USN aircraft flying over USS Zumwalt advanced guided-missile destroyer

MQ-4C, E-2C, C-2A, P-8A, F-35 and SH-60R flew over USS Zumwalt in Chesapeake

USS Zumwalt, the U.S. Navy’s newest and most technologically advanced surface ship, was commissioned in Baltimore, Maryland, on Oct. 15 during the city’s Fleet Week festivities.

First ship of a new class of stealthy multi-mission destroyers (worth $4.4 billion apiece), the futuristic Zumwalt features an advanced power system capable to generate 78 megawatts of power and has the ability to launch TLAMs (Tomahawk Land Attack Missiles) and Evolved Sea Sparrow Missiles (like those used in Yemen recently), as well as a wide array of other anti-ship and anti-submarine weaponry.

Several aircraft flew over the advanced multi-mission guided-missile destroyer as it travelled to its new home port of Sand Diego.

In this post you can find the most interesting photos.

The top one (courtesy of Naval Air Systems Command) is particularly cool. It shows a Northrop Grumman MQ-4C Triton overflying USS Zumwalt.

U.S. Navy’s MQ-4C “Triton” Broad Area Maritime Surveillance (BAMS) unmanned aircraft system (UAS), is an ISR (Intelligence Surveillance Reconnaissance) platform under development that will complement the P-8A Poseidon within the Navy’s Maritime Patrol and Reconnaissance Force family of systems.

The MQ-4C is a much advanced version than the first generation Global Hawk Block 10: it is believed to be a sort of Block 20 and Block 30 Global Hawk hybrid, carrying Navy payload.

With a 130.9-foot wingspan, the drone features an AN/ZPY-3 multi-function active-sensor (MFAS) radar system, that gives the Triton the ability to cover more than 2.7 million square miles in a single mission that can last as long as 24 hours at a time, at altitudes higher than 10 miles, with an operational range of 8,200 nautical miles.

A test proved the gigantic Navy drone’s ability to pass FMV (Full Motion Video) to a Poseidon MPA (Maritime Patrol Aircraft) last June.

The U.S. Navy plans to procure 68 aircraft and 2 prototypes.  The program received Milestone C low-rate initial production approval after a successful Milestone Decision Authority review at the end of September 2016.

161017-N-UZ648-029 CHESAPEAKE BAY, Md. (Oct. 17, 2016) An E-2D Hawkeye and a C-2A Greyhound assigned to Air Test and Evaluation Squadron (VX) 20 fly over USS Zumwalt (DDG 1000) as the ship travels to its new home port of San Diego, California. Zumwalt was commissioned in Baltimore, Maryland, Oct. 15 and is the first in a three-ship class of the Navy's newest, most technologically advanced multi-mission guided-missile destroyers. (U.S. Navy photo by Erik Hildebrandt/Released)

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CHESAPEAKE BAY, Md. (Oct. 17, 2016) An E-2C Hawkeye and a C-2A Greyhound assigned to Air Test and Evaluation Squadron (VX) 20 fly over USS Zumwalt (DDG 1000) as the ship travels to its new home port of San Diego, California. Zumwalt was commissioned in Baltimore, Maryland, Oct. 15 and is the first in a three-ship class of the Navy’s newest, most technologically advanced multi-mission guided-missile destroyers. (U.S. Navy photo by Erik Hildebrandt/Released)

 

161017-N-UZ648-054 CHESAPEAKE BAY, Md. (Oct. 17, 2016) A P-8A Poseidon assigned to Air Test and Evaluation Squadron (VX) 20 flies over USS Zumwalt (DDG 1000) as the ship travels to its new home port of San Diego, California. Zumwalt was commissioned in Baltimore, Maryland, Oct. 15 and is the first in a three-ship class of the Navy's newest, most technologically advanced multi-mission guided-missile destroyers. (U.S. Navy photo by Erik Hildebrandt/Released)

161017-N-UZ648-054
CHESAPEAKE BAY, Md. (Oct. 17, 2016) A P-8A Poseidon assigned to Air Test and Evaluation Squadron (VX) 20 flies over USS Zumwalt (DDG 1000) as the ship travels to its new home port of San Diego, California. Zumwalt was commissioned in Baltimore, Maryland, Oct. 15 and is the first in a three-ship class of the Navy’s newest, most technologically advanced multi-mission guided-missile destroyers. (U.S. Navy photo by Erik Hildebrandt/Released)

 

161017-N-CE233-334 CHESAPEAKE BAY, Md. (Oct. 17, 2016) An SH-60R assigned to Air Test and Evaluation Squadron (HX) 21 flies near USS Zumwalt (DDG 1000) as the ship travels to its new home port of San Diego, California. Zumwalt was commissioned in Baltimore, Maryland, Oct. 15 and is the first in a three-ship class of the Navy's newest, most technologically advanced multi-mission guided-missile destroyers. (U.S. Navy photo by Liz Wolter/Released)

161017-N-CE233-334
CHESAPEAKE BAY, Md. (Oct. 17, 2016) An SH-60R assigned to Air Test and Evaluation Squadron (HX) 21 flies near USS Zumwalt (DDG 1000) as the ship travels to its new home port of San Diego, California. Zumwalt was commissioned in Baltimore, Maryland, Oct. 15 and is the first in a three-ship class of the Navy’s newest, most technologically advanced multi-mission guided-missile destroyers. (U.S. Navy photo by Liz Wolter/Released)

 

An F-35 Lightning II Carrier Variant (CV) piloted by U.S. Marine Corps Maj. Robert "Champ" Guyette II, a test pilot from the F-35 Pax River Integrated Test Force (ITF) assigned to the Salty Dogs of Air Test and Evaluation Squadron (VX) 23, flies over the stealth guided-missile destroyer USS Zumwalt (DDG 1000) as the ship transits the Chesapeake Bay on Oct. 17, 2016. USS Zumwalt, the Navy's newest and most technologically advanced surface ship, joined the fleet Oct. 15. The F-35C Lightning II — a next generation single-seat, single-engine strike fighter that incorporates stealth technologies, defensive avionics, internal and external weapons, and a revolutionary sensor fusion capability — is designed as the U.S. Navy’s first-day-of-war, survivable strike fighter. The U.S. Navy anticipates declaring the F-35C combat-ready in 2018. (U.S. Navy photo by Andy Wolfe/Released)

An F-35 Lightning II Carrier Variant (CV) piloted by U.S. Marine Corps Maj. Robert “Champ” Guyette II, a test pilot from the F-35 Pax River Integrated Test Force (ITF) assigned to the Salty Dogs of Air Test and Evaluation Squadron (VX) 23, flies over the stealth guided-missile destroyer USS Zumwalt (DDG 1000) as the ship transits the Chesapeake Bay on Oct. 17, 2016. USS Zumwalt, the Navy’s newest and most technologically advanced surface ship, joined the fleet Oct. 15. The F-35C Lightning II — a next generation single-seat, single-engine strike fighter that incorporates stealth technologies, defensive avionics, internal and external weapons, and a revolutionary sensor fusion capability — is designed as the U.S. Navy’s first-day-of-war, survivable strike fighter. The U.S. Navy anticipates declaring the F-35C combat-ready in 2018. (U.S. Navy photo by Andy Wolfe/Released)

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Take a look at this cool drawing of the Northrop Low Altitude Penetrator concept

This is how the B-2 LAP “variant” could have looked.

In 1979, Northrop began studies for a low-observable strategic bomber that would eventually result in the B-2 “Spirit” stealth bomber as we know it.

However, in the early days, two basic mission profiles were studied for the new aircraft: high altitude penetration and low altitude penetration.

High altitude penetration allowed a much more efficient aircraft and resulted in the genesis of the B-2’s long-span flying wing; eventually, the high-altitude penetrator flying wing was selected and modified to fill the low-altitude penetrator role.

Based on the research and the subsequent Autocad line drawings by Scott Lowther over at Aerospaceprojectsreview.com, Kurt Beswick has illustrated the Northrop LAP (Low Altitude Penetrator) concept that you can find in this post (please note that although the B-2 was the successor of the high and low altitude penetrator concepts, the artist has dubbed it “B-2 LAP,” a designation we have kept in this article.)

Vaguely reminding a Boeing study for a low-altitude stealth bomber dating back to 1979 Beswick’s LAP is a reviewed version of what is believed to be the basic design on which Northrop’s low altitude penetrator studies focused back in the 1970s.

Needless to say, there’s no evidence, that such an aircraft would look like that if built, but the shape is cool and the artist’s impression is somehow realistic (with elements reminding the triangle-shaped objects spotted over the U.S. a couple of years ago).

The illustration represents a concept that never made it past the design-stage : this does not mean something eventually made it into other “black projects.”

Here’s how Beswick explains the LAP concept:

“I have taken some artistic liberties, including the updated markings and details. All the rest is speculative and based upon the performance requirements set forth by the USAF in the 1979-1980.”

Here’s the description provided by Scott Lowther to the original line drawing:

“Low-altitude penetration resulted in a less efficient aircraft with a much higher wing loading.

The low-altitude penetrator Northrop examined was something between a flying wing and a lifting body.

It would fly at high-speed and ultra-low altitude, much like an enormous cruise missile. As a result, it needed to be minimally visible to detection systems in aircraft positioned above it. Thus, the upper surface of the aircraft was largely featureless with the exception of the cockpit.

The underside featured both the flush inlet and engine exhaust in a flattened configuration, as well as two inward-canted vertical stabilizers. The high wing loading meant that the aircraft would need 200 knots airspeed for takeoff, consuming nearly 8,000 feet of runway. Total onboard fuel load would be 137,500 pounds requiring a few refuelings for each mission.”

Dealing with the color scheme, Beswick opted for the same livery of the Spirit:

“After discussing with my pilot buddies, they all agree that this aircraft would be no different in coloration than a B-2 or B-1, charcoal/dark gray-blue.”

Click below to download the hi-rez version of the rendering.

LAP

Image credit: Kurt Beswick

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The U.S. Air Force has revealed the first image of its future Long Range Strike bomber: the B-21

Here is the Northrop Grumman B-21, quite similar to the Northrop Grumman B-2.

On Feb. 26, Air Force Secretary Deborah Lee James revealed the first artist rendering of the Long Range Strike Bomber, an aircraft built by Northrop Grumman and designated the B-21, at the Air Force Association’s Air Warfare Symposium in Orlando, Florida.

The aircraft, that was not given a name yet, is going to be the first stealth bomber of the 21st century: it will supplement the B-52, B-1 and B-2, with the latter (another Northrop Grumman design) sharing much resemblance with the future LRS-B.

In particular, the aircraft seems to be designed around a standard flying wing: neither a “cranked kite” nor a kite like those seemingly spotted over the Wichita and Amarillo back in 2014.

As you probably remember, on Mar. 10, 2014 Steve Douglass and Dean Muskett took the photographs of three mysterious planes flying at very high altitude over Amarillo, Texas.

The three unknown planes looked like boomerang-shaped plane.

About one month later (on Apr. 15), Jeff Templin shot a triangular plane over Wichita Kansas.

Among the theories around both episodes there was the one that the aircraft were LRS-B prototypes. But according to what was unveiled earlier today there no prototypes of the next generation stealth bomber and its shape is going to be much different from that of the aircraft flying at high altitude over the U.S. in 2014.

Hence, the mystery around those sightings remains.

Texas-vs-Kansas-mystery-planes

Image credit: Sammamishman based on Muskett and Templin shots

“The platforms and systems that made us great over the last 50 years will not make us great over the next 50,” Air Force Chief of Staff Gen. Mark A. Welsh III said during his testimony on Capitol Hill Feb. 10. “There are many other systems we need to either upgrade or recapitalize to ensure viability against current and emerging threats… the only way to do that is to divest old capability to build the new.”

There are no existing prototypes of the B-21, most of its capabilities are still unknown even though the aircraft is (obviously) believed to embed cutting edge technologies and sensors and to be cyber-resilient against the threats of the future interconnected world.

The artist rendering released on Feb. 26 is based on the initial design concept: this means the actual plane may be considerably different.

The Air Force plans to field the initial capability of the aircraft around 2025.

Image credit: U.S. Air Force