F-35 Lightning II developments

[Coati]

First AIM-120 AMRAAM release by a F-35A from Edwards.

http://www.youtube.com/watch?v=cQeBgdoiTa4

[Coati]

And another first flight of a LRIP-4 aircraft. AF-21 is marked 422 TES and has tailcode OT. So this one (and AF-22 and others) will soon go to Nellis AFB.

Lockheed Martin test pilot Paul Hattendorf is at the controls for the first flight of F-35A AF-21 (US Air Force serial number 10-5009) on 20 October 2012. The flight was from NAS Fort Worth JRB.

http://www.codeonemagazine.com/news_ite ... tem_id=888

Of the other OT registered F-35A's the first one AF-17, assigned to 31 TES was already delivered to Eglin in July 2012

[Coati]

Just a few days away of the first delivery of active service USMC F-35Bs:


Marines Get Ready For F-35 Ops At Yuma
By Amy Butler
Source: Aerospace Daily & Defense Report

October 22, 2012
The U.S. Marine Corps is preparing to begin operations for the first operational F-35 squadron next month at MCAS Yuma, Ariz., and officials are optimistic for a mid-month standup despite some challenges ahead.

Key to starting up squadron operations will be a small but growing cadre of maintainers, pilots and aircraft, says Col. Kevin Killea, aviation requirements branch head for the Marine Corps.

The first F-35B is expected at Marine Fighter Attack Sqdn. 121 in early November, with the second slated for delivery mid-month. These will be the first low-rate-initial-production aircraft delivered from prime contractor Lockheed Martin to the Defense Department, and these aircraft will include the 1B software. A total of 16 F-35Bs, the number needed for full operational capability, are expected at the base within the next year, Killea says.

Six pilots have been tapped for early operations at Yuma, as well. They are currently in various stages of training; some are already qualified to use the 1A software and simply need to get “difference training” between the two blocks. Killea says small group tryouts are slated for November to determine which two of five pilots in the first 1B class at Eglin AFB, Fla., where pilot training is handled, will be among those first six pilots selected for ops at Yuma.

But to begin operations, the Marine Corps must continue to implement a foundation for the squadron’s infrastructure at the base, including delivery of the Autonomic Information Logistics System (ALIS) Block 1.03. Last month, Maj. Gen. Christopher Bogdan, F-35 deputy program director, pointed out that the squadron will not be able to properly stand up without this system. ALIS is a comprehensive system of hardware and software used to manage the F-35, including health and diagnostics of each aircraft, supply tasks and mission planning. The 1.03 release is critical for Yuma because it includes the security features needed to conduct classified operations; Killea notes that Eglin is using ALIS 1.02 because the training base doesn’t need to access classified flight data. An operational squadron, however, cannot function without it.

Lockheed Martin has had problems with ALIS 1.03 owing to security vulnerabilities. Killea says that the work “has come a long way in the last couple of months,” and what could have been a six-month slip was compressed to allow for standup of the squadron next month.

The Marines still decline to outline a specific initial operational capability (IOC) date for the F-35B. IOC will require 10 F-35Bs available for ship- or land-based deployment and surge options. That also will include the appropriate number of pilots and two-shift maintenance operations, Killea says.

IOC is tied somewhat to release of the Block 2B F-35 software. But Killea says the Marines will withhold an IOC declaration until all of the needed capabilities—such as basic close-air-support and interdiction activities as well as initial air-to-air and data-linking—are delivered, whether they are included in Block 2B or a subsequent release.

http://www.aviationweek.com/Article.asp ... 509033.xml

[Coati]

BF-21, BuNo 168719 coded VK-01 first flight was on 24 October. This is the first aircraft destined for a front line squadron, USMC squadron VMFA-121...which unit is expecting this first aircraft in early November.

My earlier post on delivery of the first OT aircraft to Eglin is doubtful. Still at Fort Worth I presume...

[Stratofreighter]

http://www.codeonemagazine.com/f35_news ... tem_id=887

Spin Chute Ground Test

Posted 20 October 2012

Lockheed Martin test pilot David Nelson is at the controls of F-35A test aircraft AF-4 for the first ground deployment test of the spin recovery parachute on 20 October 2012.

The test took place on Runway 22 at the Air Force Test Center at Edwards AFB, California. The spin recovery system is a safety device required for upcoming high angle of attack flight tests.

[Arjan]

Apperently RAF nr.2 has been delivered to Eglin. ZM136

http://www.af.mil/news/story.asp?id=123323935

[Coati]

Apperently RAF nr.2 has been delivered to Eglin. ZM136

http://www.af.mil/news/story.asp?id=123323935

Already posted at 20 Oct.

[Arjan]

Must have missed it in between those 15 pages

[sdamico]

if all F-35A will have an USAF serial , may be all F-35B will have a BuNo

any info about BuNo for ZM135 and ZM136?

The October 2012 issue of Air International has an article on the F-35 in which ZM135 is also referenced as 168315.

The issue also says that static test article AG-1 returned to Fort Worth from the UK in August.

Regarding AF-17 thru -20, haven't these gone (or are going) to Edwards (not Eglin)?: http://www.f-16.net/f-16_forum_download-id-16499.html.

SD

[Bennie]

From the Dutch 'regeerakkoord':

Mede op basis van beide rapportages zal het kabinet eind 2013 een beslissing nemen over de vervanging van de F16. Gelet op het rapport van de Algemene Rekenkamer ter zake zetten we de ontwikkel- en testprogramma’s conform de MOU’s voort.

Translation: based on both reports (mentioned elsewhere in the 'regeringsakkoord) a decision regarding the replacement of the F16 will be made. Having considered the report of the 'Algemene Rekenkamer (= financial gurus) on this matter the development and testingprogrammes will be continued in accordance with the MOUs (= F35 investments).

[Piet Luijken]

Summary 5 by Lockheed:

The F-35 Flight Test Update in the Volume 27, Number 2 issue of Code One concluded with the record-setting month of June 2012 with the Integrated Test Force completing 114 test flights and 1,118 test points. Since then, the team set new records of 135 System Development and Demonstration, or SDD, flights for 239 SDD flight hours and more than 1,100 test points in August 2012. With training pilot checkouts at Eglin AFB, Florida, and test pilot qualifications at NAS Patuxent River, Maryland, fifty-four pilots have now flown the F-35 Lightning II.

Weapon testing has progressed since the last issue as F-35 pilots dropped the program’s first 1,000- and 2,000-pound inert Joint Direct Attack Munitions, or JDAMs, and the first AIM-120 AMRAAM separation test was carried out. The team also completed airstart testing for the F-35A and F-35B variants to collect critical data for upcoming high angle of attack tests. Through 20 October 2012, the F-35 program had accrued 986 test flights for more than 7,800 test points in 2012.

9 July 2012: First F-35B Night Flight
US Marine Corps pilot Maj. Richard Rusnok took off in F-35B BF-2 at 9:57 p.m. EDT for the B-model’s first night flight. The one-hour flight from NAS Patuxent River, Maryland, in BF-2 evaluated the aircraft’s exterior lighting. It was Flight 204 for BF-2.

17 July 2012: First F-35C Flight With Block 2A Software
The first F-35C test mission with updated Block 2A software was piloted by Navy Lt. Chris Tabert in F-35C CF-3 for 1.1 hours from NAS Patuxent River, Maryland. Block 2A software provides additional capabilities for the F-35, such as the Multifunction Advanced Datalink, the current Link-16, maintenance datalink, and a mission debriefing system. The mission marked CF-3 Flight 68.

27 July 2012: F-35A Airstart Testing Complete
Lockheed Martin test pilot David Nelson completed airstart testing in F-35A AF-4 during Flight 131 over the Edwards AFB, California, test range. The 2.3-hour mission included the final four required airstarts, a critical step prior to the start of high angle of attack tests.

1 August 2012: First Air-To-Air MADL Exchange
F-35As AF-3 and AF-6 accomplished a high data rate exchange with the first F-35 air-to-air communication over the Multifunction Advanced Datalink, or MADL. Air Force Lt. Col. George Schwartz flew AF-3 on Flight 128 for two hours from Edwards AFB, California. Mark Ward piloted the 1.8-hour AF-6 Flight 104.

7 August 2012: First F-35B Airstart Mission
Marine Corps Lt. Col. Matt Kelly piloted the three first F-35B engine spooldowns over the Edwards AFB, California, test range to signal the beginning of F-35B airstart testing. The 1.3-hour mission marked F-35B BF-2 Flight 212.

8 August 2012: First Weapons Separation
Flying at 400 knots at 4,200 feet altitude in F-35B BF3, Lockheed Martin test pilot Dan Levin dropped an inert 1,000-pound GBU-32 JDAM over the Atlantic test range. The 0.8-hour mission was the F-35 program’s first weapon separation. The milestone flight was BF-3 Flight 224.

10 August 2012: First F-35C Fly-In Arrestment
Navy Lt. Chris Tabert accomplished the first fly-in arrestment into the MK-7 arresting gear cable by an F-35C at JB McGuire-Dix-Lakehurst, New Jersey. Using an interim arresting hook system, an engineering team composed of F-35 Joint Program Office, Naval Air Systems Command, and industry officials conducted tests to assess cable dynamics, aircraft loads, and performance on F-35C CF-3. During testing, Tabert achieved five of eight attempts into the arresting gear. Completing these tests enabled the F-35 program to improve the redesigned arresting hook system. Engineering design reviews will continue, culminating in initial sea trials projected for spring 2014.

13 August 2012: New Record 19 Flights In One Day
The F-35 program set a new record of nineteen flights in one day in production flights and test flights at five bases across the United States. F-35s were flown from Edwards AFB, California; NAS Patuxent River, Maryland; JB McGuire-Dix-Lakehurst, New Jersey; NAS Fort Worth JRB, Texas; and Eglin AFB, Florida.

15 August 2012: F-35B Airstarts Complete
Lockheed Martin test pilot Dan Canin piloted F-35B BF-2 for Flight 217 to perform the F-35B’s final airstart test mission. Pilots accomplished twenty-seven F-35B airstarts over the Edwards AFB, California, test range to complete the prerequisite for next year’s F-35B high angle of attack tests.

17 August 2012: BF-2 Returns To Pax
The F-35B test aircraft BF-2 was ferried back to NAS Patuxent River, Maryland, with Dan Canin at the controls following the completion of airstart testing. After an overnight stop at NAS Fort Worth JRB, Texas, Canin completed the trip from Edwards AFB, California, with 3.4-hour BF-2 Flight 219.

22 August 2012: F-35B Formation Flight
Marine Corps Maj. C. R. Clift and Navy Lt. Cmdr. Michael Burks flew F-35B test aircraft BF-2 and BF-4 in formation over the Atlantic Test Range. The flight, which originated from NAS Patuxent River, Maryland, tested formation flying qualities at subsonic and supersonic speeds to provide data on F-35B handling characteristics. The 1.9-hour mission marked BF-2 Flight 221 and BF-4 Flight 130.

22 August 2012: 20,000th Test Point Complete
The SDD team accomplished 20,000 test points since the beginning of the test program with two F-35A test flights at Edwards AFB, California, and three F-35B test flights at NAS Patuxent River, Maryland. The overall F-35 SDD flight test program plan calls for 59,585 test points to be verified through developmental test flights by 31 December 2016.

23 August 2012: 1,000th F-35A Test Flight
The F-35A test fleet marked the program’s 1,000th conventional takeoff and landing test flight during three test missions at Edwards AFB, California.

27 August 2012: F-35B Radar Cross Section Testing Complete
Marine Corps Maj. Richard Rusnok piloted F-35B BF-5 for a 1.2-hour flight to complete baseline testing of the aircraft’s radar cross section on a series of flights from NAS Patuxent River, Maryland. The flight marked BF-5 Flight 51.

31 August 2012: New Flight Test Records
The F-35 test team accomplished 135 SDD flights for 239 SDD flight hours and more than 1,100 test points for a record-setting month in August.

12 September 2012: Five Jets Airborne At Pax
The Integrated Test Force at NAS Patuxent River, Maryland, flew five simultaneous test missions: F-35B BF-2, BF-3, BF-4, and BF-5; and F-35C CF-2.

13 September 2012: 2,000 F-35A Flight Hours
The F-35 program’s 2,000th F-35A conventional takeoff and landing test flight hour on a 1.9-hour mission systems sortie occurred in F-35A AF-7 on its 123rd flight. Air Force Maj. Eric Schultz was at the controls for the milestone flight from Edwards AFB, California.

24 September 2012: External Weapons Formation Flight
Air Force Maj. Eric Schultz and Maj. Brent Reinhardt flew F-35A aircraft AF-1 and AF-2 in formation with external inert AIM-9X missiles. The 1.3-hour test flight measured formation flying qualities. The sorties, AF-1 Flight 250 and AF-2 Flight 279, originated from Edwards AFB, California.

4 October 2012: Pax Adds A Pilot
Marine Corps Capt. Michael Kingen joined the test pilot roster at NAS Patuxent River, Maryland, with his 0.9-hour check flight. The first flight for the fifty-fourth F-35 pilot was F-35C CF-3 Flight 85.

4 October 2012: Production Jet Joins Pax Fleet
An F-35 production jet landed at NAS Patuxent River, Maryland, for the first time when F-35B BF-17 was ferried from NAS Fort Worth JRB, Texas, with Bill Gigliotti at the controls. BF-17 will temporarily support the Integrated Test Force at Pax until it joins the Operational Test team at Edwards AFB, California. The 3.1-hour ferry flight marked BF-17 Flight 8.

16 October 2012: First F-35A Weapon Release
The F-35A completed the conventional takeoff and landing variant’s first inflight weapon release at China Lake, California. The weapon release followed the first F-35B weapon release in August. Air Force Maj. Eric Schultz released an inert, instrumented 2,000-pound GBU-31 from the aircraft’s left weapon bay over the Naval Air Warfare Center Weapons Division ranges. The 1.3-hour mission, originating from Edwards AFB, California, marked F-35A AF-1 Flight 254.The F-35 Flight Test Update in the Volume 27, Number 2 issue of Code One concluded with the record-setting month of June 2012 with the Integrated Test Force completing 114 test flights and 1,118 test points. Since then, the team set new records of 135 System Development and Demonstration, or SDD, flights for 239 SDD flight hours and more than 1,100 test points in August 2012. With training pilot checkouts at Eglin AFB, Florida, and test pilot qualifications at NAS Patuxent River, Maryland, fifty-four pilots have now flown the F-35 Lightning II.

Weapon testing has progressed since the last issue as F-35 pilots dropped the program’s first 1,000- and 2,000-pound inert Joint Direct Attack Munitions, or JDAMs, and the first AIM-120 AMRAAM separation test was carried out. The team also completed airstart testing for the F-35A and F-35B variants to collect critical data for upcoming high angle of attack tests. Through 20 October 2012, the F-35 program had accrued 986 test flights for more than 7,800 test points in 2012.

9 July 2012: First F-35B Night Flight
US Marine Corps pilot Maj. Richard Rusnok took off in F-35B BF-2 at 9:57 p.m. EDT for the B-model’s first night flight. The one-hour flight from NAS Patuxent River, Maryland, in BF-2 evaluated the aircraft’s exterior lighting. It was Flight 204 for BF-2.

17 July 2012: First F-35C Flight With Block 2A Software
The first F-35C test mission with updated Block 2A software was piloted by Navy Lt. Chris Tabert in F-35C CF-3 for 1.1 hours from NAS Patuxent River, Maryland. Block 2A software provides additional capabilities for the F-35, such as the Multifunction Advanced Datalink, the current Link-16, maintenance datalink, and a mission debriefing system. The mission marked CF-3 Flight 68.

27 July 2012: F-35A Airstart Testing Complete
Lockheed Martin test pilot David Nelson completed airstart testing in F-35A AF-4 during Flight 131 over the Edwards AFB, California, test range. The 2.3-hour mission included the final four required airstarts, a critical step prior to the start of high angle of attack tests.

1 August 2012: First Air-To-Air MADL Exchange
F-35As AF-3 and AF-6 accomplished a high data rate exchange with the first F-35 air-to-air communication over the Multifunction Advanced Datalink, or MADL. Air Force Lt. Col. George Schwartz flew AF-3 on Flight 128 for two hours from Edwards AFB, California. Mark Ward piloted the 1.8-hour AF-6 Flight 104.

7 August 2012: First F-35B Airstart Mission
Marine Corps Lt. Col. Matt Kelly piloted the three first F-35B engine spooldowns over the Edwards AFB, California, test range to signal the beginning of F-35B airstart testing. The 1.3-hour mission marked F-35B BF-2 Flight 212.

8 August 2012: First Weapons Separation
Flying at 400 knots at 4,200 feet altitude in F-35B BF3, Lockheed Martin test pilot Dan Levin dropped an inert 1,000-pound GBU-32 JDAM over the Atlantic test range. The 0.8-hour mission was the F-35 program’s first weapon separation. The milestone flight was BF-3 Flight 224.

10 August 2012: First F-35C Fly-In Arrestment
Navy Lt. Chris Tabert accomplished the first fly-in arrestment into the MK-7 arresting gear cable by an F-35C at JB McGuire-Dix-Lakehurst, New Jersey. Using an interim arresting hook system, an engineering team composed of F-35 Joint Program Office, Naval Air Systems Command, and industry officials conducted tests to assess cable dynamics, aircraft loads, and performance on F-35C CF-3. During testing, Tabert achieved five of eight attempts into the arresting gear. Completing these tests enabled the F-35 program to improve the redesigned arresting hook system. Engineering design reviews will continue, culminating in initial sea trials projected for spring 2014.

13 August 2012: New Record 19 Flights In One Day
The F-35 program set a new record of nineteen flights in one day in production flights and test flights at five bases across the United States. F-35s were flown from Edwards AFB, California; NAS Patuxent River, Maryland; JB McGuire-Dix-Lakehurst, New Jersey; NAS Fort Worth JRB, Texas; and Eglin AFB, Florida.

15 August 2012: F-35B Airstarts Complete
Lockheed Martin test pilot Dan Canin piloted F-35B BF-2 for Flight 217 to perform the F-35B’s final airstart test mission. Pilots accomplished twenty-seven F-35B airstarts over the Edwards AFB, California, test range to complete the prerequisite for next year’s F-35B high angle of attack tests.

17 August 2012: BF-2 Returns To Pax
The F-35B test aircraft BF-2 was ferried back to NAS Patuxent River, Maryland, with Dan Canin at the controls following the completion of airstart testing. After an overnight stop at NAS Fort Worth JRB, Texas, Canin completed the trip from Edwards AFB, California, with 3.4-hour BF-2 Flight 219.

22 August 2012: F-35B Formation Flight
Marine Corps Maj. C. R. Clift and Navy Lt. Cmdr. Michael Burks flew F-35B test aircraft BF-2 and BF-4 in formation over the Atlantic Test Range. The flight, which originated from NAS Patuxent River, Maryland, tested formation flying qualities at subsonic and supersonic speeds to provide data on F-35B handling characteristics. The 1.9-hour mission marked BF-2 Flight 221 and BF-4 Flight 130.

22 August 2012: 20,000th Test Point Complete
The SDD team accomplished 20,000 test points since the beginning of the test program with two F-35A test flights at Edwards AFB, California, and three F-35B test flights at NAS Patuxent River, Maryland. The overall F-35 SDD flight test program plan calls for 59,585 test points to be verified through developmental test flights by 31 December 2016.

23 August 2012: 1,000th F-35A Test Flight
The F-35A test fleet marked the program’s 1,000th conventional takeoff and landing test flight during three test missions at Edwards AFB, California.

27 August 2012: F-35B Radar Cross Section Testing Complete
Marine Corps Maj. Richard Rusnok piloted F-35B BF-5 for a 1.2-hour flight to complete baseline testing of the aircraft’s radar cross section on a series of flights from NAS Patuxent River, Maryland. The flight marked BF-5 Flight 51.

31 August 2012: New Flight Test Records
The F-35 test team accomplished 135 SDD flights for 239 SDD flight hours and more than 1,100 test points for a record-setting month in August.

12 September 2012: Five Jets Airborne At Pax
The Integrated Test Force at NAS Patuxent River, Maryland, flew five simultaneous test missions: F-35B BF-2, BF-3, BF-4, and BF-5; and F-35C CF-2.

13 September 2012: 2,000 F-35A Flight Hours
The F-35 program’s 2,000th F-35A conventional takeoff and landing test flight hour on a 1.9-hour mission systems sortie occurred in F-35A AF-7 on its 123rd flight. Air Force Maj. Eric Schultz was at the controls for the milestone flight from Edwards AFB, California.

24 September 2012: External Weapons Formation Flight
Air Force Maj. Eric Schultz and Maj. Brent Reinhardt flew F-35A aircraft AF-1 and AF-2 in formation with external inert AIM-9X missiles. The 1.3-hour test flight measured formation flying qualities. The sorties, AF-1 Flight 250 and AF-2 Flight 279, originated from Edwards AFB, California.

4 October 2012: Pax Adds A Pilot
Marine Corps Capt. Michael Kingen joined the test pilot roster at NAS Patuxent River, Maryland, with his 0.9-hour check flight. The first flight for the fifty-fourth F-35 pilot was F-35C CF-3 Flight 85.

4 October 2012: Production Jet Joins Pax Fleet
An F-35 production jet landed at NAS Patuxent River, Maryland, for the first time when F-35B BF-17 was ferried from NAS Fort Worth JRB, Texas, with Bill Gigliotti at the controls. BF-17 will temporarily support the Integrated Test Force at Pax until it joins the Operational Test team at Edwards AFB, California. The 3.1-hour ferry flight marked BF-17 Flight 8.

16 October 2012: First F-35A Weapon Release
The F-35A completed the conventional takeoff and landing variant’s first inflight weapon release at China Lake, California. The weapon release followed the first F-35B weapon release in August. Air Force Maj. Eric Schultz released an inert, instrumented 2,000-pound GBU-31 from the aircraft’s left weapon bay over the Naval Air Warfare Center Weapons Division ranges. The 1.3-hour mission, originating from Edwards AFB, California, marked F-35A AF-1 Flight 254.

19 October 2012: First F-35 AMRAAM Jettison
F-35A test aircraft AF-1 accomplished another testing milestone with the program’s first aerial release of an AIM-120 AMRAAM. Air Force Maj. Matthew Phillips jettisoned the instrumented AIM-120 from the aircraft’s internal weapon bay over the Naval Air Warfare Center Weapons Division test range at China Lake, California, during a one-hour mission. AF-1 Flight 255 originated from Edwards AFB, California.

[ Post made via Mobile Device ]

[Coati]

Hicks said VMA-121 is expected to get its first F-35s on Nov. 20, and should have an entire squadron of planes by late spring or early summer. The next squadron to receive its new planes will be VMA-211, which lost six of its Harrier jets during an insurgent attack in September in Afghanistan.

http://www.yumasun.com/news/hicks-82944 ... adron.html

[Coati]

BF-18 departed Fort Worth for delivery to Paxutent River to boost the SDD test program. Earlier this year BF-17 was delivered to PAX as well.

Test force is now:
6 F-35A at Edwards: AF-1, 2, 3, 4, 6, 7
7 F-35B at Pax BF-1, 2, 3, 4, 5, 17, 18
3 F-35C at Pax CF-1, 2, 3
Next few months the SDD will be further reinforced with two F-35Cs: CF-5 and CF-8.

A total of 18 F-35s will then be active for SDD testing.

Meanwhile, flight operations at Eglin are ramping up:

Eglin Completes 500TH F-35 Sortie

EGLIN AIR FORCE BASE, Fla., Nov. 5, 2012 – The Integrated Training Center (ITC) here completed its 500th combined sortie for both the F-35A conventional takeoff and landing (CTOL) and F-35B short takeoff and vertical landing (STOVL) aircraft Friday. Flight operations for the F-35 began on the Emerald Coast March 6. There are currently 22 F-35s at Eglin as the fleet continues to grow supporting the team as it trains instructor pilots and maintainers. The team accomplished the 500 sorties in 238 days cutting the time between each milestone sortie:

100th sortie – July 12 - accomplished in 123 days
200th sortie – Aug. 24 - accomplished in 44 days
300th sortie – Sept. 21 - accomplished in 28 days
400th sortie – Oct. 16 - accomplished in 25 days
500th sortie – Nov. 2 - accomplished in 16 days

[Coati]

And another one takes to the sky (6Nov2012), AF-24 10-5012/OT:

http://www.codeonemagazine.com/f35_news ... tem_id=899

Lockheed Martin test pilot Bill Gigliotti was at the controls for the first flight of F-35A AF-24. The flight occurred on 6 November 2012 from NAS Fort Worth JRB in Texas.


My guess is that the next aircraft on the line, AF-25 will be the first aircraft to be assigned to a front line squadron of Nellis.

[Coati]

http://www.codeonemagazine.com/f35_news ... tem_id=904

AF-23 took to the sky the 7th of November, serial 10-5011/OT, destined to go to 422 TES