MILAVIA Forum - Military Aviation Discussion Forum

Author Topic: F-15e flies with new radar system  (Read 10892 times)

Offline aeroorigami

  • Pilot
  • **
  • Posts: 18
F-15e flies with new radar system
« on: February 20, 2011, 03:02:08 PM »





Officials took a step forward in the F-15E Strike Eagle's continuous technological evolution as the Air Force's most versatile combat aircraft here Jan. 18.

Officials from the 46th Test Wing launched the fourth generation fighter for the first time with a new and improved radar system, the APG-82(V)1.

The APG-82 uses active electronically scanned array radar technology composed of numerous small solid-state transmit and receive modules. The standard radar, APG-70, is a mechanically scanned array housed in the nose of the aircraft. Although the current F-15E radar has undergone numerous updates and upgrades, it is still the same system the aircraft had on its maiden flight more than 24 years ago.

"We've been able to get more out of it, but at this point it's pretty much maxed out," said 1st Lt. Nathaniel Meier, a radar modernization project manager with the Operational Flight Program Combined Test Force.
The new radar lacks the motors and hydraulics of the old system and includes a new avionics and cooling system.

Aircraft radar continuously sends out and receives energy to identify objects or targets around it.
Due to its unique capabilities, the F-15E radar operates as air-to-air and air-to-ground radar, officials said.
"One AESA-equipped F-15E can detect and track multiple targets simultaneously and gain the same battle picture and prosecute the same number of attacks that currently require several mechanically scanned radar assets," said Brad Jones, the Boeing director for U.S. Air Force development programs. "Adding AESA multiplies the effectiveness of the F-15E."

The advantage AESA radar has over an MSA is its near-instantaneous ability to redirect its focus from air-to-air to air-to-ground mode, officials said.
By no longer having to wait for the array to physically move to a new area of interest, the aircrew receives better situational awareness in less time, Lieutenant Meier said.

The four-year-old project borrowed from existing technology to create the new system. The array system was taken from F-15C Eagle models and the avionics were borrowed from F-18 Hornets.
The reason for the change was to improve the entire aircraft's reliability, availability and maintainability, Lieutenant Meier said.

The new radar works as a plug-in-play system with newer, easily replaceable parts, the lieutenant said.
It's expected to have approximately a 20-fold improvement in aircraft reliability, he said.
The aircraft also stays mission-ready.
An average failure for the radar component was previously measured in tens of hours and can now be measured in hundreds of hours, Lieutenant Meier said.

The APG-82 has fewer moving parts and the new equipment lasts longer, which cuts down on the time needed for repairs, he said.
The modification of the aircraft, which began in June 2010, was a concerted effort by members of Boeing, the 46th Maintenance Group, Raytheon, the 46th Technical Support Squadron and the OFP CTF.
"Without their determination, (F-15E) RMP would not have been anywhere close to making its first flight," Lieutenant Meier said.

The developmental test flight was considered successful, and the aircrew members said they liked what they saw during the flight.
"There are huge performance increases," said Maj. Raja Chari, a 40th Flight Test Squadron member and the pilot for the first flight. "We're getting the benefit of two decades worth of technology. From what we saw in this flight, we're heading in the right direction."
The developmental test process is about building incrementally into testing more complicated functions of the equipment and finding any flaws and problems based on usage in specific test profiles.
"Really, the engineers put in the time and hard work," Major Chari said. "We have the easy part of seeing if it will do what they thought it would. It was interesting to see the engineers reacting and diagnosing the issues right away, based on our feedback."
Capt. Chris Dupin, a 40th FTS member and the weapons system officer for the first flight, said he noticed improved capabilities during the initial flight.
He said the radar was able to detect F-16s much farther away than ever before.
"The kill chain for anything is the ability to detect, identify, target and engage a threat," Captain Dupin said. "If we can detect an air target earlier or farther away, that leaves more time and space to complete the rest of the kill chain. Completing the kill chain faster and earlier means we're better able to gain or maintain airspace superiority."
The biggest "test" facing the project involves combining avionics and array systems from other aircraft and incorporating them into a totally different one.
"By using (government and commercial) off-the-shelf equipment, the Air Force is able to save a large amount of the development costs, but the challenge is integrating these new systems and making them work as one," Lieutenant Meier said.
Developmental testing is scheduled to continue through 2012, but the OFP CTF, being a shared unit of the 46th Test Wing and 53rd Wing, is unique in that its members can perform developmental tests while incorporating early operational testing.
Officials have begun modifying a 53rd Wing F-15E with the new radar and they plan to begin some of the operational type of testing as early as March.
The next stage of testing for the radar will be conducted by Air Force Operational Test and Evaluation Center officials before being incorporated in all F-15Es beginning in approximately 2014.

DEFENCE TALK

Offline vanaheim

  • Recruit
  • *
  • Posts: 3
Re: F-15e flies with new radar system
« Reply #1 on: March 07, 2011, 11:26:28 AM »
I first heard about this when the Su-30MKI was having some combined wargames with Eagles. But it seems to me this technology appeared first on the MiG-31 and then on the Su-35/34. Certainly the processing capabilities of the US aircraft have traditionally proven greatly superior, but I'm not really up on the latest Russian limited production batches. Supposed to be pretty good too.

Offline Webmaster

  • MILAVIA Webmaster
  • Administrator
  • General of Flight
  • *******
  • Posts: 2842
  • Country: nl
Re: F-15e flies with new radar system
« Reply #2 on: March 07, 2011, 03:58:41 PM »
Welcome vanaheim!

I'm not really into the technical aspects, but the passive electronical scanned arrays are simpler than its active, more modern, counterparts. In PESA multiple transmit/receive components use one radiation generator, whereas in AESA each T/R module has its own radiation generator. I'm not really familar with the tech, but I think this difference makes AESA (better) able to support simultaneous multi-mode/multi-channel operations. Although the latest PESA (Irbis) has improved a lot, I think this results in AESA giving far better situational awareness and tracking multiple targets. From what I've seen, I do think the Russians are putting more emphasis on having a powerful main beam for (very) long-range tracking. I'm not sure how AESA compares in that respect, as I would imagine the radiation is less powerful or it becomes really expensive (and demanding in terms of power and cooling I guess). So I could definately see PESA like approach being more suitable for some systems (E-3, bombers, interceptors), I think for multi-role tactical aircraft AESA is the better solution.

Whether PESA or AESA, beam steering is often limited, mechanical steering of the array can greatly improve the sphere. I would definately like to see more of that. The "less moving parts, fewer maintenance" benefit doesn't apply then, so I guess that explains that we haven't seen it much on the latest upgrades. I guess to have it fixed also gives more room for more T/R modules.

  • Interests: Su-15, Su-27, Tu-22, Tornado, RNLAF
Niels Hillebrand
MILAVIA Webmaster

Offline Webmaster

  • MILAVIA Webmaster
  • Administrator
  • General of Flight
  • *******
  • Posts: 2842
  • Country: nl
Re: F-15e flies with new radar system
« Reply #3 on: March 07, 2011, 04:22:26 PM »
And the Russian also have their AESA development. I'm not sure where they are at, I would imagine the PAK-FA getting AESA. But I've only seen one solid offering in form of the Zhuk-AE, which is offered on the MiG-33/35. It seemed to be more powerful per module than most US AESA radars, so it looks promising. On larger fighters, there's room for improvement due to larger diameter permitting more modules and more power available. But so far it's only developments I think.
  • Interests: Su-15, Su-27, Tu-22, Tornado, RNLAF
Niels Hillebrand
MILAVIA Webmaster

Offline shawn a

  • Hero of Flight
  • ******
  • Posts: 898
  • Country: us
Re: F-15e flies with new radar system
« Reply #4 on: March 07, 2011, 09:19:41 PM »
How about distributed aperture arrays? I know the -15 doesn't have that, but I thouight the PAK-FA, and the F-35 were supposed to have that system.
I can only surmise that the benefit would be much better coverage angles at the cost of raw power.
Perhaps one of you more erudite folks can explain why cooling is such an issue, since the air at altitude is famously cold, and even approaching stall speeds of most modern aircaraft there is significant airflow to use. however, even I have noticed there don't seem to be any intakes for cooling air anywhere near the radars of most planes. (E-2 aside)

Offline Webmaster

  • MILAVIA Webmaster
  • Administrator
  • General of Flight
  • *******
  • Posts: 2842
  • Country: nl
Re: F-15e flies with new radar system
« Reply #5 on: March 08, 2011, 12:18:57 AM »
ow, I just imagined that becoming an issue with powerful electronics so tightly packed together in such a confined space, but yeah maybe you are right and it isn't an issue as the heat can be conducted away to the frame. ma bad.
  • Interests: Su-15, Su-27, Tu-22, Tornado, RNLAF
Niels Hillebrand
MILAVIA Webmaster

Offline Webmaster

  • MILAVIA Webmaster
  • Administrator
  • General of Flight
  • *******
  • Posts: 2842
  • Country: nl
Re: F-15e flies with new radar system
« Reply #6 on: March 08, 2011, 12:29:13 AM »
How about distributed aperture arrays? I know the -15 doesn't have that, but I thouight the PAK-FA, and the F-35 were supposed to have that system.

True, but they don't have the range/power of the main radar unit.
  • Interests: Su-15, Su-27, Tu-22, Tornado, RNLAF
Niels Hillebrand
MILAVIA Webmaster

Offline shawn a

  • Hero of Flight
  • ******
  • Posts: 898
  • Country: us
Re: F-15e flies with new radar system
« Reply #7 on: March 08, 2011, 05:57:29 AM »
No, Niels, not at all yer bad, I've read repeatedly that cooling is a major issue with avionics, I just wonder WHY, with all that cold air available.
In another vein, how about using one pair of AAM fins as the pylon, so when the missile is gone, the stealth remains. (Of course, the missile and it's fins would have to be somewhat stealthy to begin with) Sounds doable to me.

Offline Webmaster

  • MILAVIA Webmaster
  • Administrator
  • General of Flight
  • *******
  • Posts: 2842
  • Country: nl
Re: F-15e flies with new radar system
« Reply #8 on: March 08, 2011, 01:50:41 PM »
I looked at some MiG-31 images, the main bay showed a lot of line-replaceable units, but plenty of room to allow air to circulate (not the smallest aircraft though).

I'm thinking the air in the compartment is cold, but the heating issues occur within the LRU themselves.
  • Interests: Su-15, Su-27, Tu-22, Tornado, RNLAF
Niels Hillebrand
MILAVIA Webmaster

Offline Webmaster

  • MILAVIA Webmaster
  • Administrator
  • General of Flight
  • *******
  • Posts: 2842
  • Country: nl
Re: F-15e flies with new radar system
« Reply #9 on: March 08, 2011, 02:24:05 PM »
In another vein, how about using one pair of AAM fins as the pylon, so when the missile is gone, the stealth remains. (Of course, the missile and it's fins would have to be somewhat stealthy to begin with) Sounds doable to me.

Bit off-topic...

you want to be stealthy before your attack not afterwards. but ok, let's think about it.

Your missile may not require a launch rail then, meaning it's suitable for carriage inside a bay or (semi-)recessed anyway. Aside from that, pylons provide clearance for the flaps/ailerons where needed, so if you want to do without them, your missile requires large fins, while development thanks to TVC and fly-by-wire allows small fins in turn producing smaller cross section. It has to support the weight (or rather forces), so your fin needs to be reinforced. It has to be a non-moving fin, or have a lock mechanism, otherwise the weapon will swivel while suspended, would be fun to see though. Unless you use a larger umbilical cord, you also need to fit your data+power connector to the top of the fin. Also,  unless it's not too long, it still does not fit under the outer wing section, unless you'd want to add a fin in the middle? If carried on stations where it didn't replace a large pylon in the first place...it increases RCS more than a semi-recessed AAM would.

Pylons can be made stealthy. I don't see why you'd build a special AAM to get rid of them. You'd still need to develop pylons for launch rail type weapons and everything else in the inventory without the Shawn-fins.  ;)

I'd say it's over-engineering to get rid of something simple and multi-purpose, without fully solving the (small)problem it presented.
« Last Edit: March 08, 2011, 02:27:08 PM by Webmaster »
  • Interests: Su-15, Su-27, Tu-22, Tornado, RNLAF
Niels Hillebrand
MILAVIA Webmaster

 



AVIATION TOP 100 - www.avitop.com click to vote for MILAVIA