Breaking News: Iran Shoots Down a US RQ-4A Global Hawk Drone

Lucas Tomlinson, the Pentagon reporter for Fox News, has confirmed what was shot down over the Straits.

US officials confirm that US RQ-4A Global Hawk drone was shot down by an Iranian surface-to-air missile this evening while operating within international airspace over the Strait of Hormuz.

There are several reports that the unmanned aircraft was a US Navy Northrop Grumman MQ-4C Triton which is an American high-altitude long-endurance unmanned aerial vehicle flown by the United States Navy as a surveillance aircraft.

Other reports indicate that the MQ-4C has not been operationally deployed and that there are none known to be in the Middle East region. Tyler Rogoway is reporting on the Wardrive website that this was a U.S. Air Force RQ-4 Global Hawk UAV that Iran shootdown.

Either way, this is a serious escalation of events in the Middle East and in the Straits of Hormuz in particular. More as we get it.

More on this story via The UK Sun at https://www.thesun.co.uk/news/9334596/iran-shoots-down-us-spy-drone-tensions-gulf/

US Air Force RQ-4 Global Hawk flew over Ukraine ADS-B transponder turned on

In an article posted on The Aviationist website by David Cenciotti, he is reporting that the U.S. Air Force’s gigantic Global Hawk drones have been flying over Ukraine for about two years. However, they recently let everyone  know they were there.

Aircraft serial number #04-2021 turned on its ADS-B transponder on October 15 using hex address AE27A7 while flying over Ukraine at 50175 feet squawking 5527.

U.S. RQ-4Bs belonging to the 9th Operations Group/Detachment 4th of the U.S. Air Force deployed to Sigonella from Beale Air Force Base, California, have been flying ISR (Intelligence Surveillance Reconnaissance) missions in support of EUCOM, AFRICOM and CENTCOM theater mission tasking since 2011.

You can read David's entire article at https://theaviationist.com/2016/10/18/u-s-air-force-rq-4-global-hawk-drone-flew-over-ukraine-with-transponder-turned-on-for-everyone-to-see/

100K & Going: Airmen at Grand Forks AFB help reach Global Hawk flying milestone

By Staff Sgt. Luis Loza Gutierrez,  319th Air Base Wing Public Affairs

GRAND FORKS AIR FORCE BASE, N.D. -- Although the days of the bombers and tankers are long gone, Airmen at Grand Forks Air Force Base, N.D., are still finding ways to make Air Force history thanks to the Global Hawk mission.

The Northrop Grumman Corporation recently announced its high-altitude, long-endurance unmanned aircraft systems achieved 100,000 flight hours Sept. 5.

News of the milestone was well-received by the leadership and members of the 69th Reconnaissance Group, the unit at Grand Forks AFB directly in charge of conducting Global Hawk missions.

"This milestone is something in which those of us involved in the Global Hawk mission take great pride," said Col. Lawrence Spinetta, 69th RG commander.

According to Northrup Grumman, approximately 88 percent of the 100,000 flight hours for this aircraft were logged by U.S. Air Force Global Hawks. Credit for the remaining flight hours was split among the NASA Global Hawks, the German EURO HAWK®, and the U.S. Navy's Broad Area Maritime Surveillance Demonstrator and Triton UAS.

The Global Hawk also has the safest record of any fighter, bomber or reconnaissance aircraft in the Air Force's active inventory.

According to statistics from the Air Force Safety Center, as of Sept. 3, 2013, the RQ-4 reached the 100,000-flight hour milestone without a fatality, a huge advantage of unmanned aircraft technology. Additionally, it enjoyed the fewest Class A and Class B mishaps.

"The safety record of the U.S. Air Force Global Hawk fleet is remarkable, especially given the fact that the system was rushed to combat and flew 75 percent of its first 100,000 hours supporting our warfighters in Afghanistan and elsewhere," Spinetta said. "These figures prove the reliability of unmanned aircraft technology. More importantly, it's testament to the professionalism of our Airmen and the pride they take in accomplishing our mission."

The Global Hawk is aptly named. Every day, RQ-4s circle the globe, providing critical strategic intelligence, surveillance, and reconnaissance to six combatant commands.

"The jet's long endurance is a significant combat force multiplier," Spinetta said.

The RQ-4, which can fly for upwards of 30 hours nonstop, has the ability to cover almost half the circumference of the world without refueling. That capability makes it a key contributor to the global vigilance, global reach, and global power of the U.S. Air Force.

Spinetta reflected on the recent aviation milestone and contemplated what it means for the history of the Air Force.

He told members of the 69th RG that their hard work is "the realization of an Air Force prophecy" by Gen. Henry H. "Hap" Arnold. As the commanding general for the U.S. Army Air Force in 1945, Arnold said, "We have just won a war with a lot of heroes flying around in planes. The next war may be fought by airplanes with no men in them at all...Take everything you've learned about aviation in war, throw it out the window, and let's go to work on tomorrow's aviation."

Members of the 69th RG will receive patches from Northrop Grumman commemorating the milestone.

"Some people might refer to the patch as badge of honor, however, we know the real honor is knowing we are doing an excellent job protecting our warriors and our nation," Spinetta said. "That's exactly what we will continue to do."

Air Force officials use Global Hawk to support Japan relief efforts

An RQ-4 Global Hawk like the one pictured is being used to assist Japan in disaster relief and recovery efforts. (U.S. Air Force photo/Senior Airman Nichelle Anderson)

JOINT BASE PEARL HARBOR-HICKAM, Hawaii (AFNS) -- Pacific Air Forces officials are using an RQ-4 Global Hawk from Andersen Air Force Base, Guam, to assist Japan responders in disaster relief and recovery efforts, following the March 11 earthquake and the resulting tsunami off the eastern coast of Japan.

The Global Hawk, a high-altitude, long-endurance unmanned aircraft, is being used to help assess damage to towns, industrial infrastructure and other facilities affected during the earthquake and flood waters.

"The Global Hawk is an ideal ISR asset to aid in disaster relief," said Gen. Gary North, the PACAF commander. "It directly complements ongoing efforts in the region and represents how advanced technology can provide crucial and timely support to senior officials and search, recovery and disaster relief efforts."

The Global Hawk also was used for disaster relief efforts following the 7.0-magnitude earthquake that struck Haiti in January 2010, officials said. This will be the aircraft's first use in a humanitarian operation in the Pacific theater since it was permanently assigned at Andersen AFB in September 2010.

With approximately 30 hours of flight endurance, the Global Hawk provides a broad view of the situation on the ground, officials said. Its ability to survey large geographic areas also offers decision-makers and first responders near real-time information to assess damage and prioritize for local need. Its long airborne dwell capacity also assures continuous and long-lasting-support for whatever requirements Japan's government officials may require.

"The Global Hawk and the expertise offered by our Airmen further enhances the country's already robust capabilities as our Air force members work side by side with Japan's Self Defense Force professionals," General North said.

The aircraft allows the U.S. to effectively support contingencies throughout the region, demonstrating a commitment to partners throughout the Pacific, and is one part of a wide range of PACAF personnel and aircraft that are supporting the Japanese operations, officials said.

Global Hawk arrives in Guam

by Tech. Sgt. Mike Andriacco, 36th Wing Public Affairs

ANDERSEN AIR FORCE BASE, Guam -- Airmen here celebrated the arrival of the RQ-4 Global Hawk to Guam during a ceremony Sept. 20.

The Global Hawk brings significant capabilities to the Pacific theater, which will benefit the 36th Wing, Pacific Air Forces, U.S. Pacific Command, and regional partners, said Gen. Gary North, the PACAF commander.

"Having an (intelligence, surveillance and reconnaissance) capability within the Pacific greatly enhances Air Force operational intelligence capabilities to meet mission requirements," General North said. "In addition, the Global Hawk will enhance the U.S. and its partners' ability to effectively address regional challenges, such as humanitarian assistance, disaster relief, terrorism and piracy."

The Global Hawk is capable of providing government and military decision makers near real-time, high-altitude, long-range intelligence, surveillance and reconnaissance imagery that can support a full spectrum of operations. Flying above ordinary commercial traffic, the aircraft can survey large geographic areas with pinpoint accuracy, without impacting civilian aircraft routes. The imagery provides the most current information available during contingency or crisis situations.

"This is a technology that saves lives," said Lt. Col. Brandon Baker, the Air Combat Command Det. 3 commander. "The RQ-4 has been used in contingency operations and humanitarian missions before. During wildfires in California, the Global Hawk provided firefighters with a near real-time view of the crisis and helped firefighters and rescue personnel direct their efforts."

In January, the Global Hawk also provided imagery to coordinators of the international disaster relief and humanitarian mission in Haiti's earthquake.

"Basing the RQ-4 at Andersen will support ongoing regional partnerships and reaffirm to U.S. friends, allies and partner nations of our commitment to continue modernization efforts and force structure beddown to support maintaining peace and stability in the region," General North said.

So far, one of three planned Global Hawks has arrived here. The remaining two are scheduled to arrive later this year and at the beginning of 2011. Local crews will launch and land the aircraft from here, while crews at Beale AFB, Calif., will control the bulk of the mission, once out of the local area.

"We'll be flying missions in support of U.S. Pacific Command priorities," Colonel Baker said. "We also intend to share with our allies information pertaining to common regional challenges like humanitarian assistance, disaster relief and piracy."

The Global Hawk has flown more than 45,000 hours worldwide since becoming operational in 1995. The remotely piloted aircraft is flown using a variety of communications protocols, complete with built-in safety measures in the event that communication between the mission control and the aircraft is lost.

In the event that all communication with the aircraft is lost or it encounters an in-flight emergency, the Global Hawk is programmed to continue its flight to its original destination or return to its point of origin and land. During this time, the pilot may be able to reestablish a link to the aircraft. If that is impossible, the Global Hawk is capable of landing on its own.

"The aircraft is flown by fully qualified, certified U.S. Air Force pilots -- a fact which contributes to the RQ-4's unparalleled safety record," Colonel Baker said. "The RQ-4 negotiates pre-programmed flight plans and the pilots communicate with air traffic controllers in a similar manner as pilots in manned aircraft."

Deployed Global Hawks surpass 30,000 combat flying hours, 1,500 sorties

by Master Sgt. Scott T. Sturkol, 380th Air Expeditionary Wing Public Affairs

SOUTHWEST ASIA (AFNS) -- One of the largest unmanned aerial systems operating in the U.S. Central Command area of responsibility, the RQ-4 Global Hawk, surpassed 30,000 combat flying hours and 1,500 combat sorties Feb. 10 here.

The Global Hawks are assigned to the 380th Air Expeditionary Wing from Beale Air Force Base, Calif. They provide a broad spectrum of intelligence, surveillance and reconnaissance collection capability to support joint combatant forces in worldwide peacetime, contingency and wartime operations.

The 380th AEW Global Hawks reached their 1,500th combat sortie on Feb. 10.

The historic sortie and flying hour mark nearly coincided, said Capt. Michelle Campbell, the lead aircraft maintenance officer for the 380th Expeditionary Aircraft Maintenance Squadron's Hawk aircraft maintenance unit.

"When our 1,500th combat sortie completed we were at 29999.4 hours," Captain Campbell said. "On our very next sortie the next night (Feb. 11), as soon as the (Global) Hawk cleared the airfield, that's when we reached 30,000."

The RQ-4 arrived to this deployed location in October 2001, shortly after the events of Sept .11, 2001, said Senior Master Sgt. Timothy Green, the 380th EAMXS Hawk AMU superintendent.

"The aircraft has been a constant presence here since then providing high altitude-long endurance ISR to the combatant commander," Sergeant Green said. "The significance of 30,000 combat hours and 1,500 flights is high. This began as a test platform and was never intended to fly that many sorties or hours. Because of the capability the RQ-4 brought, it has been able to pave the way for a future generation of RQ-4s and has driven the overall (UAS) programs to even greater heights than expected."

At the core of the RQ-4's capabilities is its ability to take photos using its integrated sensor suite.

Tech. Sgt. Edward Andrews, a Global Hawk avionics systems craftsman with the 380th EAMXS Hawk AMU also deployed from the 9th AMXS at Beale AFB, said his primary job with the airframe is to care for the "center package."

That package includes sensors comprised of synthetic aperture radar, electro-optical and medium-wave infrared sensors.

The RQ-4 reaching these historical achievements speaks volumes for those who maintain them, Sergeant Andrews said.

"The Hawk AMU knows every day we have to prep the Global Hawk for an important mission, a mission to help troops on the ground which in turn helps save lives," said Sergeant Andrews, who has helped prepare the (aircraft system) for more than 110 combat sorties. "I like what I do because it is such a unique role and so few Airmen have a part in something like this."

Another RQ-4 maintainer with the 380th EAMXS, Staff Sgt. Michael Goenner, prepared the Global Hawk on more than 50 combat missions.

"The aircraft has to be ready to go every day," said Sergeant Goenner, who helped with the both historic launches on Feb. 10 and 11. "We finish our pre-flight servicing checks every day to make sure everything is good to launch for the next mission."

"It's an honor to be involved and to see it become accomplished. For an airframe that was never supposed to go this long, we are essentially making history every day we use it," Sergeant Goenner said.

For Airmen 1st Class Jessica George and Rueben Mendoza, both RQ-4 cyber transport specialists with the Hawk AMU from the 9th AMXS at Beale AFB, knowing they had a part in the success of the Global Hawk's achievements is special.

"When it actually happened, I didn't realize it," said Airman George, who cares for the launch recovery element that guides the RQ-4 in flight. "We come in and work hard every day. The historic launches weren't our focus, but looking back I'm glad I was here for it."

"I enjoy setting up everything for our missions," Airman Mendoza added. "Being here while that took place is something I will definitely remember."

Sergeant Green said the aircraft has proved its capability and the importance of that capability to the theater of operations more than 10-fold.

"Throughout those 30,000 combat hours, the aircraft has provided near real time
imagery to meet strategic planning across the full spectrum of the battlefield," Sergeant Green said. "The key to its success falls on the shoulders of the young men and women of the Hawk AMU. Maintaining an aircraft this new has many challenges.

"These young Air Force maintainers, combined with field service representative support, were able to set record maintenance rates to include two-plus years without a single cancellation for maintenance," Sergeant Green said. "This is key to persistent ISR in the theater."

"Our guys have been doing an absolutely awesome job here," Captain Campbell added. "They are among some of the best groups of people I've ever had the pleasure to work with. I can't say enough about them."

Airmen provide intelligence, surveillance, reconnaissance

Airmen quickly remove the final pins from a U-2 before a flight Oct. 4, 2009. The sortie was Capt. Peter J. Gryn's first combat mission. The U-2 is the primary source of high-altitude intelligence, surveillance and reconnaissance. Captain Gryn is deployed from Beale Air Force Base, Calif. (U.S. Air Force photo/Staff Sgt. J.G. Buzanowski)

by Staff Sgt. J.G. Buzanowski, U.S. Air Force Central combat camera team

SOUTHWEST ASIA (AFNS) -- Leaders at every level need battlefield information, and because of Airmen with the 99th Expeditionary Reconnaissance Squadron ... now they know.

With their RQ-4 Global Hawk and U-2 aircraft, the Airmen excel at providing intelligence, surveillance and reconnaissance for everyone from combatant commanders to troops on the ground.

According to Lt. Col. Kirt Stallings, the squadron commander, their mission is as much a tactical one as it is strategic. The pilots provide leaders with the knowledge they need to make more informed decisions about operations. But the pilots also communicate with joint terminal attack controllers embedded with Army and Marine units, as well as coalition partners.

"When a pilot is overhead, they can talk directly to troops so if guys on the ground need to know what's beyond that next ridge, we can let them know," said Colonel Stallings, a Houston native. "If a JTAC on the ground needs air support, a U-2 pilot can let them know what assets are available for that as well."

Both the U-2 and Global Hawk, deployed from Beale Air Force Base, Calif., have a plethora of sensors, but each aircraft is used in different ways. The U-2 flies above 70,000 feet so it's able to record both signals and still imagery intelligence over a larger area. But because the Global Hawk doesn't have an onboard pilot, it can stay overhead longer than the typical ten hour U-2 sorties.

"Global Hawks and U-2s complement each other," Colonel Stallings explained. "For example, if a U-2 pilot finds four different hot spots that need monitoring, they can reach out to other assets, like Global Hawks, to provide ISR needs. A U-2 is more capable, but a Global Hawk can remain on station after a U-2 has to turn back."

The Global Hawk pilots in theater are responsible for the takeoff and landing; operators back at Beale actually give it commands during most of its mission. Keeping the bulk of Global Hawk operations stateside means a smaller footprint at their deployed location, Maj. Scott Zeller said.

"Having some RQ-4 pilots in theater is a safety net to make sure launches and recoveries go smoothly," said Major Zeller, a Denver native. "Once the aircraft is in the air, we hand-off operations to the pilots back at Beale and they can fly it for the next 20 hours from there."

Unmanned aerial systems provide "an amazing capability" for coalition forces, Major Zeller said. Those capabilities will only get better in the future. The squadron is currently preparing for the newest version of the aircraft, which boasts a larger wingspan and upgraded sensors.

"The Global Hawk is the future of the high-altitude ISR mission," said New Jersey native Maj. Andrew McVicker, the 99th ERS director of operations. "But in the interim, nothing compares to what the U-2 can do. The most impressive thing about our community is that we've been flying the U-2 for more than 50 years and it's just as important today as ever -- it's the stalwart of the battlefield.

"Either way, ISR keeps commanders in the know," Major McVicker said, "and knowing is half the battle."

Global Hawk flying mapping missions south of border

by Tech. Sgt. Eric Petosky, 12th Air Force (Air Forces Southern) Public Affairs

DAVIS-MONTHAN AIR FORCE BASE, Ariz. (AFNS) -- The RQ-4 Global Hawk unmanned aircraft is currently using its sensors for non-military environmental mapping missions over South, Central America and the Caribbean at the request of partner nations in the region.

The flights, dubbed "eco-missions" by the Air Forces Southern team, provide vital training to aircrews while supplying partner nations with high-quality, multi-spectrum imagery to be used by local governments.

The aerial photography is used for a variety of purposes, from counter-drug operations and disaster response planning to monitoring deforestation, urbanization and beach erosion, depending on what the requesting country is interested in tracking.

"Unfortunately, hurricanes, earthquakes and flooding occur regularly in the AFSOUTH area of focus," said Lt. Gen. Norman Seip, 12th Air Force (Air Forces Southern) commander. "The chance to share with partner nations high-resolution imagery greatly enhances their ability to generate disaster response plans and to assess long-term environmental issues -- this program is a prime example of how regional challenges can be overcome using new technology, creativity and cooperation."

Six eco-missions were flown in fiscal 2008, and 12 are scheduled to be flown in fiscal 2009, according to Thomas Schnee, 12th AF (AFSOUTH) deputy chief of operational planning. The electro-optical and infrared cameras provide high-resolution imagery within the focus of coverage.

"We've turned a traditional intelligence, surveillance and reconnaissance platform into a theater security cooperation partnership success," Mr. Schnee said. "This is completely transparent, permissive over flight of countries who request imagery products."

Airborne imagery from the Global Hawk platform has been used in the United States to track the effects of natural disasters such as wildfires and hurricanes. By comparing pictures of an area taken at different intervals, major environmental changes can be detected early. In cases of natural disasters, helicopter routes and landing sites can be identified in remote areas early to speed up the response times of emergency responders.

The Global Hawk is based at Beale Air Force Base, Calif. All flights to the AFSOUTH area of focus originate and terminate at Beale AFB. Due to the distances involved, the flight times through international air space can leave little time to collect images. Mr. Schnee said, in the future, having regional refueling locations with ground crews will increase the range and duration of Global Hawk missions. Currently, the unmanned system can spend up to 30 hours in the air for a single mission.

Airmen demonstrate unmanned aircraft not merely 'drones'

by Staff Sgt. Zachary Wilson, AFCENT Combat Camera News Team

KANDAHAR, Afghanistan (AFNS) -- The door to the 62nd Expeditionary Reconnaissance Squadron features a drawing of an MQ-1 Predator armed with Hellfire missiles underscored with the words "We're not drones - we fire back."

Often referred to by reporters as "drones," unmanned aircraft like the MQ-1 Predator and RQ-4 Global Hawk are remotely-flown weapons systems flown both locally and stateside from ground stations using satellite uplinks. They're also far more complex than the U.S. military's relatively more simplified radio-controlled drone aircraft used for aerial target practice, according to unmanned aircraft system professionals.

For the Airmen flying and maintaining the lethal Predator and its big brother, the MQ-9 Reaper, from Kandahar Air Field, Afghanistan, and from Creech Air Force Base, Nev., the message is demonstrated to their adversaries on a regular basis.

"(Both the MQ-1 and MQ-9 are weapons-carrying aircraft,) and both have a hunter-killer role in addition to their intelligence, surveillance and reconnaissance capabilities," said Lt. Col. Scott Miller, the 62nd ERS commander, who is deployed from the 432nd Air Expeditionary Wing at Creech AFB.

Performing dual-missions of close-air support and ISR taskings, the Predator can stay airborne for more than 12 hours at 50,000 feet and the Reaper can stay up for a longer period of time at even higher altitudes, according to squadron officials. Boasting a full-motion video camera with various modes that can detect enemy movements, the Predator and Reaper also carry the Hellfire missile. In addition to carrying a larger payload of Hellfires, the UAs bring to the fight a set of two 500 lbs. laser-guided bombs that allow operators to not only observe and detect hostile forces, but also eliminate them if called upon to do so.

"Both aircraft can initiate and complete the 'killchain'," Colonel Miller said. "With their ability to loiter for long periods of time over a target, eliminate it, stay on station and then provide the (bomb damage assessment,) they provide continuity to a mission and prove to be invaluable assets."

The aircraft are flown jointly by the 62nd ERS crews stationed here with the 451st Air Expeditionary Group and by crews back at Creech using satellite uplinks that transfer control from the local pilots who taxi, launch, land and recover the aircraft (all from trailers adjacent to the flightline) and the Creech aviators flying inside of mission control elements performing missions across Afghanistan. British Royal Air Force counterparts also fly the Reaper.

General Atomics contractors perform maintenance on the Reaper while responsibility for Predator maintenance is undertaken by 62nd ERS Airmen.

"As this aircraft is like 90 percent avionics, it's a pretty unique experience to work on it," said Senior Airman Doug Cox, a 62nd ERS MQ-1 avionics specialist from Creech AFB. "We're asked to do a lot more than our traditional specialties and most of us are trained up on crew chief duties such as performing 60-hour inspections, changing spark plugs, engine oil and things like that."

First Lt. Andrew Dowd, also deployed from Creech AFB as the unit's maintenance officer, agreed.

"This aircraft does not have hydraulic fluid and operates using electro-servos," he said, also noting the aircraft recently reached a 500,000 flight hour milestone. "It's a very unique platform, but of course, when it's all said and done, it's the $1.2 million camera that runs the show."

After the aircraft are airborne and are handed off by the Kandahar crew, Creech aviators perform the majority of traditional mission taskings. However, the 62nd ERS Airmen increasingly are taking responsibility for executing missions within the local area to aid and protect coalition forces stationed around Kandahar who are fighting the enemy. Sometimes weapons are dropped, demonstrating the lethality and uniqueness of the 62nd ERS' mission and aircraft to friends and foes alike.

Notably, some missions are often generated to fly only within the local area, putting the responsibility for the entire mission on the shoulders of the Kandahar-based aircrews.

It's great to have a direct impact on the war," said Airman 1st Class Patrick Snyder, an MQ-9 sensor operator who maneuvers the system's cameras and sensors as well as directs its munitions when launched. "We provide over-watch for the Canadians fighting the Taliban and then have coffee with them at the end of day (here at Kandahar.) It really makes us feel connected."

Capt. Ryan Jodi, a B-1 pilot who now flies the Reaper from his cockpit position in a ground control element, also acknowledged his preference for performing missions locally as opposed to Creech.

"I really enjoy doing the launches and landings from here," he said. "It really gives you more of a flying feeling. And doing local missions is also great because we can really appreciate the camaraderie we have with our coalition partners who we live with here."

With spring arriving in Afghanistan, Taliban and Al Qaeda insurgents once again will ramp up hostile operations against coalition forces around the country as they have demonstrated each year during the duration of Operation Enduring Freedom.

However, with the planned increase of forces within the area, that means more assets are on the way, with 62nd ERS leaders preparing for additional aircraft and more mission sorties generated from combatant commanders. With nearly 10 additional Reapers coming to supplement the squadron's approximately dozen MQ-9 aircraft, Colonel Miller says that means more work.

"In 2005, we were generating about two sorties a day," he said. "We've more than quadrupled that now and we are going to expect a lot more coming in the future."

Col. Ted Osowski, the 451st AEG commander, agreed with Colonel Miller on the demand for the ISR hunter/killer platforms in-theater.

"No other asset is more sought after," he said. "Close air support and ISR are very valuable to the ground commanders."