Aerial refueling improvement ideas and resources

Air-to-Air Refueling seen from an F-16 cockpit.

These are some aerial refueling improvement ideas as well as links to various related resources. Currently (December 2014) FlightGear both have several aircraft that can be refueled and several tankers. However there is room for improvement.

Current situation

(December 2014)

• At least the MRTT AI tanker have parts that are "hot"/possible to collide with.

Boom refueling

• None of the tankers have lights indicating the aircraft position in the boom envelope or refueling status.
• Few, if any of the tankers have a moving boom.

Drogue and probe refueling

• None of the tankers have lights indicating the aircraft position or refueling status.
• The hose is fixed length and rigid.

Ideas on improvements

• Adding refueling status lights to all tankers (red, amber and green)

Drogue and probe refueling

• Borrowing code etc. used for towing gliders
  • Visualize the hose using parts or the entire towing code
  • Have the hose attached to the nacelle and the probe (with a small braking force, 320 pounds (MA-2) or 550 pounds (MA-3 and MA-4))
  • Visualize the drogue at the end of the hose

Meanings of the pod lights

From ATP-56(A) (November 2000)

Phase	Lights			Meaning	Country/Aircraft
	Red	Amber	Green
Before contact	Steady	-	-	Do not make contact	AUS/B707-338C, CAN/CC130T, FRA/C135 FR, FRA/C160 NG, GER/TOR, ITA/TOR, ITA/B707/320 T/T, ESP/KC130H, ESP/B707 T/T, GBR/Tristar, GBR/VC10C, USA/KC135 MPRS, USA/KC-10, USA/KC-130, OMEGA/KC-707
Before contact	-	Steady	-	Tanker ready for contact	AUS/B707-338C, CAN/CC130T, FRA/C135 FR, FRA/C160 NG, FRA/ETD/SUE, GER/TOR, ITA/TOR, ITA/B707/320 T/T, SAF/B707/320C, ESP/KC130H, ESP/B707 T/T, GBR/Tristar, GBR/VC10C, USA/KC135 MPRS, USA/KC-10, USA/KC-130, USA/S-3B, OMEGA/KC-707
Before contact	Flashing	-	-	Don not connect	SAF/B707/320C
Before contact	Flashing	-	-	Break away	CUSA/KC135 MPRS, USA/KC-10
In contact	Steady	-	-	Remain in contact and standby for instructions	AUS/B707-338C
In contact	Steady	-	-	No fuel flow	OMEGA/KC-707
In contact	Steady	-	-	Disconnect and standby for instructions	CAN/CC130T, ESP/B707 T/T, USA/KC-130
In contact	Steady	-	-	Break away	GBR/Tristar, GBR/VC10C
In contact	Flashing	-	-	Disconnect	AUS/B707-338C, FRA/C160 NG, ESP/KC130H
In contact	Flashing	-	-	Break away	CAN/CC130T, ITA/TOR, ITA/TOR, SAF/B707/320C, ESP/B707 T/T, USA/KC135 MPRS, USA/KC-10, OMEGA/KC-707
In contact	Flashing/steady	-	-	Break away	ITA/B707/320 T/T
In contact	-	-	-	No fuel flow/dry contact	AUS/B707-338C
In contact	-	-	-	Transfer complete/disconnect	USA/KC-10
In contact	-	-	-	No fuel flow; soft contact, disconnect	ITA/B707/320 T/T
In contact	-	-	-	Dry contact/transfer complete	FRA/C135 FR, USA/KC135 MPRS
In contact	-	-	-	Don not connect/disconnect	GBR/Tristar, GBR/VC10C
In contact	-	-	Steady	Fuel flowing	AUS/B707-338C, CAN/CC130T, FRA/C135 FR, FRA/C160 NG, FRA/ETD/SUE, GER/TOR, ITA/B707/320 T/T, SAF/B707/320C, ESP/KC130H, ESP/B707 T/T, GBR/Tristar, GBR/VC10C, USA/KC135 MPRS, USA/KC-10, USA/KC-130, USA/S-3B, OMEGA/KC-707
In contact	-	Flashing	-	Hose pushed in to far	AUS/B707-338C, CAN/CC130T, FRA/C135 FR, ITA/B707/320 T/T, SAF/B707/320C, ESP/B707 T/T, USA/KC135 MPRS, USA/KC-10
In contact	-	Flashing	-	Fuel tanks full, no more fuel available, disconnect Within first minute: Soft contact, disconnect	GBR/Tristar, GBR/VC10C
In contact	-	Steady	-	Hose to far aft	FRA/C135 FR, USA/KC135 MPRS
In contact	-	Steady	-	Hose not within envelope; no fuel flow	OMEGA/KC-707
In contact	-	-	Flashing	Fuel tanks full	CAN/CC130T
In contact	-	-	Flashing	Fuel tanks full/pod malfunction	ESP/KC130H, USA/KC-130
In contact	-	-	Changing Dim/bright	Planned transfer complete, more fuel available	ITA/B707/320 T/T
In contact	-	-	Flashing	Fuel tanks full, more fuel available	GBR/Tristar, GBR/VC10C
Before contact	Flashing	-	-	Break away	CUSA/KC135 MPRS
	-	-	-

Common terminology

Terms commonly used in relevant marketing material and technical references.

Aerial refueling itself

• Air-to-air refueling (AAR) (Standard NATO term and abbreviation)
• In flight refueling (IFR)
• (fr) Ravitaillement en vol

Technical terms

Boom drogue adapter (BDA)

A short hose with a drogue that can be fitted to a boom.

Boom envelope

The space the boom nozzle can move around in limited by the boom extension and the boom traverse.

Coupling

The part that is attached to the hose and to which the drogue is attached and the probe connects to

Common types are the MA-2 (unregulated flow), MA-2 (regulated flow) and MA-4 (dual redundantly regulated flow). MA probably stands for Marshall Aerospace.

Nozzle

(1) The nozzle at the end of the boom.

(2) Confusingly also the probe.

Receiver

The receiving aircraft.

Compatibility between western and other aircraft

Russian smaller receiver aircraft

In among others the MiG-9E, MiG-29MST, MiG-29K/KUB, Su-24, Su-30 MKI and Su-35 uses NPP Zvezda ATG-2E series nozzles that are compliant to both Russian, US and NATO standards for probe and drogue refueling (in essence the MA-2 nozzle and MA-2, MA-3 and MA-4 couplings).[1]

Russian larger receiver aircraft

The larger Russian aircraft like Tu-95MSb Tu-142, Tu-160, A-50 and IL-86SH uses NPP Zvezda ATG-2MS series nozzles that may be compatible with the western probe and drogue refueling systems.[2][3]

Russian tankers

The Russian tankers all uses refueling pods. The pods are the NPP Zvezda UAPZ in variants for buddy refueling, and refueling lighter and heavier aircraft from tankers.

Chinese aircraft

Chinese tankers and receivers seem to use a mix of equipment originating from Russia and Britain.

Other

There is also some equipment from South African and Israeli companies that seems to be compatible to western systems.

Related content

Wiki articles

• Howto:Aerial refueling
• Howto:Implement aerial refueling capability
• Howto:Setup winch and aerotowing for JSBSim-aircraft

Forum topics

• Making drogue slave to probe after contact in AAR (First post in 24 May 2013)
• 707-xx pics (First post in 24 Oct 2013) (Also contains links to technical documentation.)
• Realistic Hose-Drogue Based Aerial Refueling (First post in 21 Nov 2013)
• More tanker problems (First post in 22 Aug 2014)
• Aerial refueling, tanker offsets and contact radius(First post in 23 Aug 2014)

Developer mailing list threads

• Air-to-air refuelling enhancement (First post in 24 February 2013)
• Air-air refueling (First post in 13 May 2013)
• Air to air refueling probe/receiver positions (First post in 29 January 2014)

Source code

Links point to the 3.2 release.

• fgdata/Nasal/tanker.nas
• fgdata/Aircraft/Generic/aar.nas
• fgdata/Nasal/towing/hitch.nas

External links

NATO handbook

• ATP-56(A) Air to Air Refuelling (AJP 3.3.4.2) (pdf). Published by US Navy. Retrieved 22 December 2014.

US military standards

• MIL-PRF-81975C, Performance Specification: Couplings, Regulated, Aerial Pressure Refueling Type MA-2, Type MA-3 and Type MA-4 (dpf). Published by EverySpec.com. Retrieved 22 December 2014. Contains the drawing of the externally equal MA-3 and MA-4 coupling on page 28.
• MIL-N-25161C, Military Specification: Nozzle, Aerial Pressure Refueling, TYPE MA-2 (pdf). Published by EverySpec.com. Retrieved 22 December 2014. Probably not that useful, but I include it anyway.

Drawings

• MS27604A, Military Standard: Nozzle - Universal Aerial Refueling Tanker Boom (pdf). Published by EverySpec.com. Retrieved 22 December 2014.
• MS24355B, Military Standard: Coupling, Reception - Type MA-2, Flight-pressure-refueling, Assembly of (ASG) (dpf). Published by EverySpec.com. Retrieved 22 December 2014.
• MS24356D, Military Standard: Nozzle - Type MA-2, Flight Pressure Refueling (ASG) (dpf). Published by EverySpec.com. Retrieved 22 December 2014.

Manufacturers of refueling equipment

• Cobham Mission Systems
• NPP Zvezda, Russia (Through Google translate)

Other

• Mike Gaines; Sergei Skrynnikov (photographer) (19 - 25 February 1992). Buddy-buddy Fencer (pdf). Published by Flight International. Retrieved 22 December 2014. Russian Su-24 Fencer air to air buddy refueling and Il-78 Midas refueling and techniques.
• Dr Carlo Kopp (27 Jan 2014). The PLA-AF's Aerial Refuelling Programs. Retrieved 22 December 2014.
• Photo of the F-35 being boom refueled Illustrating the lights under the forward tanker fuselage indicating to the receiver where he is in the boom envelope.