Northrop AGM-137 Tri-Service Standoff Attack Missile (TSSAM)

NMaude said:
zjz said:
I remembered coming across an AIAA paper that mentioned that JASSM has a pitch-up tendency during early store separation tests.
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Do you have a link?
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It was AIAA 2009-99.

But it was specifically mentioned in

T.O. 1B-52H-34-2-8

AIRCREW WEAPONS DELIVERY MANUAL (NONNUCLEAR) B-52/AGM-158 JASSM

(Manual was downloaded from the Internet)

Page 1-5

BLOW OFF WEDGES
Two expendable wedges are located on the underside
of each aft strake and held in place by pyrotechnic
retention pins. The wedges insure the missile
makes a clean separation from the aircraft and
are jettisoned from the missile after a fixed delay
following launch. Wedge separation occurs after
wings are deployed.
 
EBJet said:
Did you guys ever get to check out the display room in the 3-60 building? It had 2 full scale mockups of the air launched and ground launched versions, as well as a bunch of cool models of different aircraft that would carry it. I remember going to Seattle (actually Kent, WA) to Boeing's facility since they made the faux MLRS launcher for the Army version. Since the rear aspect LO requirements for that version was changed, essentially being a loitering missile dropping submunitions, the back end was redesigned, and it was having issues fitting properly in the launcher. Definitely was a fun program to work on, loading everything into that old Convair 580 and sending it off to the test site. From what I understand, there is a surviving example of the TSSAM (not sure which version) sitting out at Dugway.
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The multi service aspect made it a mess. As an example, YEARS into development, it was suddenly realized that the missiles would be stored on navy vessels, subject to salty air and water conditions and no requirement had been set for salt environment testing. Mission creep is a killer.
 
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rupe22 said:
The multi service aspect made it a mess. As an example, YEARS into development, it was suddenly realized that the missiles would be stored on navy vessels, subject to salty air and water conditions and no requirement had been set for salt environment testing. Mission creep is a killer.
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That sounds more like poor requirements definition than scope creep. Both can kill a project, of course.
 
From Oral history interview with John Cashen. Second Interview., 25 April 2014, Aerospace Oral History Project, The Huntington Library, San Marino, California. :


WESTWICK: One thing you mentioned last time is this Tri-Service Standoff Attack Missile, TSSAM. How does that fit into this story?

CASHEN: Well, it does because after I went back to Advanced Projects, Paul Kaminski came into my office one day, and he said, "John, can we make a design-to-cost cruise missile?" At the time Tomahawk and ALCM were costing roughly a million a pop. He wanted to know if we could do a stealthy cruise missile that was built to cost and then of course what would it cost. I thought about it for a while and brainstormed with him and said basically, yeah, we could and at that same price or less. So they offered us a contract to look at it. When it came in, instead of letting advanced projects do it, which is part of the Advanced Systems division, Kent Kresa handed it to our Ventura division, which was up in Thousand Oaks. It doesn't exist anymore. They did any aircraft that didn't have a man in it. I mean, it was that kind of silliness. They didn't have any RCS capability, no stealth design capability. Really, they didn't have any resource at all except, you know, they made inexpensive unmanned target drones. So anyway, we helped them, and we got through the first contract with a lot of pain and strain. By that time there was an RCS company created called Global Analytics. Alan Simon and Ken Perko started the company. It was down in Rancho Bernardo. It became really big, and then they sold it off. But as VP of Advanced Projects I was in a position, after committing the Advanced Systems division to support Ventura on TSSAM, of being told by my immediate supervisor, John Patierno, who is the VP of the division, that we won’t continue to do it because the Air Force didn't want any dilution of effort on the B-2. I said, "Well, we're not working on the B-2 in Advanced Projects." He said, "It doesn't matter." So I told Kent, "Don't kill TSSAM because we can't support it anymore. Let’s go get help from this company in Rancho." A particular RCS engineer I knew there was very good and I thought would be excellent to develop the design. Well, anyway, we issued a subcontract. My design for the missile was kind of along the lines of a stealthy Tomahawk in the sense that it was nose-only, okay? This guy, when he got the contract to do the RCS design work and testing—his name was Gordon Taylor—he came up with a low design that was nose and tail, a “butterfly.” So much the better. I was still on the program review board, so I was going to all the meetings. I was there for a program review with a customer, and I get there, and everybody's on the outside except the customers are in the conference room. Then the customer comes out and said, "I would like all you guys come on in here, except you," and he's pointing at Gordon Taylor. So I don’t go in, but sit down next to Gordon Taylor, and we're talking about things. Then the Ventura program manager comes out and says, "Gordon, you and your company are no longer working on this program. Your company has lost your facility security clearance." What had happened was, there was a surprise security inspection at Global Analytics. They hauled a bunch of stuff out of there, and they found enough violations to basically pull their site clearance.
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overscan (PaulMM) said:
View: https://www.youtube.com/watch?v=nQQQjYL3iUE


h/t Flateric
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What’s interesting is that this versions of the TSSAM has a single vertical tail like on the subsequent JASSM rather than twin canted tails in the patent.

EDIT: Never mind, the TSSAM patent does show a single vertical tail, must've read it incorrectly at the time.

The TSSAM patent lists Yu Ping Liu as one of the holders, and he’s a familiar name to those on the YF-23 and B-2 programs. He sadly passed several years ago.
 
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flateric said:
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Welp, I missed that post. That explains the strakes seen on the F/A-18 launch video.

Bruno Anthony said:
How does it compare to JASSM?
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The JASSM has somewhat of a similar shape as the TSSAM, although the chines are less pronounced especially at the nose, and there were no horizontal tails while the vertical tail is oriented up rather than down during flight. In fact, the JASSM bears resemblance to TSSAM but upside down, and they are both of similar size and weight.

The AGM-158A JASSM uses a less efficient turbojet, but the AGM-158B JASSM-ER uses a Williams turbofan that should capture much of the efficiency advantages of the TSSAM propulsion system.
 
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Coincidentally, I am reading "Stealth" by Peter Westwick at the moment ...

31ycQuh+EPL._SY344_BO1,204,203,200_.jpg
 
EBJet said:
Did you guys ever get to check out the display room in the 3-60 building? It had 2 full scale mockups of the air launched and ground launched versions, as well as a bunch of cool models of different aircraft that would carry it. I remember going to Seattle (actually Kent, WA) to Boeing's facility since they made the faux MLRS launcher for the Army version. Since the rear aspect LO requirements for that version was changed, essentially being a loitering missile dropping submunitions, the back end was redesigned, and it was having issues fitting properly in the launcher. Definitely was a fun program to work on, loading everything into that old Convair 580 and sending it off to the test site. From what I understand, there is a surviving example of the TSSAM (not sure which version) sitting out at Dugway.
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Yeah, I visited there. I was involved with TSSAM from February of 1989 until cancelation. The BGM-137B always had some different contours from the AGM-137A, especially since it was also a bit shorter to fit the box. The cancelation of that model was particularly frustrating because they cancelled it just before a test flight that would have seen if we had resolved problems from previous tests. The ground launch was something, it went for zero to Mach .4 in ten seconds due to two booster rockets and, as with most ground launched systems like this, you had to make certain that the thrust vector passed through the combined CG of the vehicle.
 
icyplanetnhc (Steve) said:
Welp, I missed that post. That explains the strakes seen on the F/A-18 launch video.


The JASSM has somewhat of a similar shape as the TSSAM, although the chines are less pronounced especially at the nose, and there were no horizontal tails while the vertical tail is oriented up rather than down during flight. In fact, the JASSM bears resemblance to TSSAM but upside down, and they are both of similar size and weight.

The AGM-158A JASSM uses a less efficient turbojet, but the AGM-158B JASSM-ER uses a Williams turbofan that should capture much of the efficiency advantages of the TSSAM propulsion system.
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That Williams engine is the same one TSSAM used.
 
Critical_NOX said:
S

Engineering and technology was solid as well as LOW capabilities. Mostly issues were due to trying to make this a multi-service, multi munition platform. How many systems launch from both a MLRS and aircraft platform. Most of the issues revolved around this multi launch platform and Multi munition requirements. When it worked, it was stellar, flying through a window from 100 miles away was impressive. The cost overruns doomed the system, not the engineering
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Some test failures were just bad choices, like one due to using components from a batch where over 50% of the lot acceptance tests failed. in another case, the seal on the inlet cover was too good and it wouldn't jettison. BGM-137B had the interesting challenge of swinging the vertical tail through the plume from one booster and retaining the tail's LO characteristics (booster exhaust including hot abrasive particles). We worked with the booster manufacturer and did get the problem resolved after a fair bit of testing.
 
stealthflanker said:
How does TASSM wing folds for internal stowage ? Does it fold forward or somehow backward ? Or maybe the wing have 3 sections which allows it to fold the same manner as a satellite solar panel.
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Wings folded aft and were stored under a jettisonable cover until launch for the air-launched versions. Ground-launched did not need that cover. Note that there were also jettisonable inlet and exhaust covers.
 
Wings and body are about the same, so 0.84328 m length for each wing and the body.
Height without tail fin Is about 0.6132 m, with tail fin it is 1.149 m.
In feet:
Individual wing span: 2,766666667 ft, body about the same.
Height without tail fin: 2,01 ft
Height with tail fin: 3,769685 ft

All of these figures are approximate and should be taken with a grain of salt.
 

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