Drawing Back the Curtain of Secrecy, section V.D throughV.H


1. Research and development (includes reactions involving deuterium andtritium)

a. Physics of the light elements. (51-1)

b. General statements concerning the relationship of commonly knownnuclear reactions of the light elements to developmental work onthermonuclear weapons. (51-1)

2. Thermonuclear test devices shipping and handling container notrevealing nuclear or military characteristics. When object is notspecifically identified as an atomic weapon and no other informationconcerning the nature or purpose of the object is revealed. (53-4)

3. Lithium and its compounds

a. Lithium enriched in the isotope Li6; Material up to and including1 kilogram contained Li6 total. (54-2)

b. Lithium enriched in the isotope Li7; Material up to 15 kilogramstotal contained Li7. (54-2)

c. Other normal lithium compounds. (54-2)

d. The fact that lithium, deuterium (Li6D, LiD) are used in unspecifiedthermonuclear weapons. (62-7) (See also II.Q.7.)

e. The mere fact that normal Lithium Deuteride (LinD) is used inunspecified TN weapons. (67-1) (See also II.Q.9.)

f. The assay of top product of Li6 production plant or the fact that thistop assay is used in weapons. (67-1) (See also II.Q.10.)

g. The fact that Li6H is used in unspecified weapons for hardening.(67-1) (See also II.Q.11.)

h. The fact the Li7H or LinH may be used as mockup materials in theweapons program. (67-1) (See also II.Q.12.)

i. The fact that compounds of Li6 containing tritium are used in thedesign of weapons as TN fuel. (72-11) (See also II.B.9. and II.Q.13.)

4. The date or estimate of the date when a thermonuclear weapon may be anactuality. (54-2)

5. Visible size and shape only of externally carried thermonuclear weaponswhen not identifiable as such. (57-1)

6. The size, weight and shape of some thermonuclear weapons (Anyinformation which reveals the existence of thermonuclear weapons withdiameter less than 24" or weight less than 2000 lb is classified). (59-7)

a. Size, weight and shape of some thermonuclear weapons (Anyinformation which reveals the existence of thermonuclear weaponwith diameter less than 18 inches or weight less than 690 pounds isclassified). (60-1)

b. The existence of, or the capability to design, a thermonuclear (TN)weapon assembly system with a diameter of 8 inches or more.(88-4)

7. The fact that certain of our operational missiles have thermonuclearwarheads. (62-7)

8. The fact that tests were conducted of designs which could lead to anentirely new class of U.S. weapons which could have relatively lowweights and extremely high yields, with the fission contributions decreasedto only a few percent of the total yield. (63-1) (See also V.B.5.b.)

9. The fact that the yield-to-weight ratios of the new class of weaponswouldbe more than twice that which can now be achieved in the design of veryhigh yield weapons using previously developed concepts. (63-1)

10. The United States, without further testing, can develop a warhead of50-60Mt for B-52 delivery." (63-3)

11. "... some improvement in high yield weapons design could be achievedandthat new warheads -- for example a 35 Mt warhead for our Titan II --based on these improvements could be stockpiled with confidence." (63-3)

12. The salvage value of the Mark 28 Nuclear Weapon recovered off the coastat Palomares, Spain, was $164,000. (67-4)

13. The fact that approximately 6 kgs of plutonium were involved intheGreenland accident. (68-4)

a. Best estimate of the amount of plutonium removed from the site.(68-4)

14. Information revealing the mere existence of TN devices with total yieldequal to or greater than 5 KT. (68-8)

15. The fact that the total number of Spartan and Sprint interceptorsplannedfor the 4-site option at Minuteman sites is 120 Spartans and 264 Sprints.(71-3)

16. The nuclear device to be tested in the Cannikin event is related to theoptimum development of a warhead for the Spartan missile of ourSafeguard Ballistic Missile Defense Program. The measurements of deviceperformance which will be obtained from the test are essential to ouroptimum defense deployment of safeguards for protection of ourMinuteman missile sites. (71-9) (See also V.B.3.rr.)

17. The fact that in thermonuclear (TN) weapons, a fission "primary" isusedto trigger a TN reaction in thermonuclear fuel referred to as a "secondary".(72-11)

18. The fact that, in thermonuclear weapons, radiation from a fissionexplosivecan be contained and used to transfer energy to compress and ignite aphysically separate component containing thermonuclear fuel. (79-2)

Note: Any elaboration of this statement will be classified.

19. Primary/secondary information: The identity of a designated devicenickname/acronym as a primary or secondary. (93-2) (See also V.C.8.j.)

20. Secondary information: The fact that fissile and/or fissionablematerials arepresent in some secondaries, materials unidentified except for uranium(depleted, natural, and enriched including highly enriched uranium),location unspecified, use unspecified, and weapon undesignated. (93-2)

21. Radiation case material information for unspecified weapons only:

a. The fact of use of specific elements with atomic number (Z) greaterthan 71 as radiation case materials. (93-2)

b. The fact of use of specific unclassified alloys as radiation casematerials. (93-2)


1. The fact that DOE weapon laboratories are engaged in a research programto explore the feasibility of a nuclear explosive driven directed energyweapon. (82-2)

2. The fact that research is being conducted on the specific concept of anuclear pumped X-ray laser. (82-2)

3. Information concerning Nuclear Directed Energy Weapons (NDEW).

a. The fact that the DOE is interested in or conducting research onNDEW concepts of certain specified generic types of output; i.e.,visible light, microwaves, charged particles, kinetic energy. (85-4)

b. The fact that underground tests at the Nevada Test Site have beenand are a part of the NDEW research program. (85-4) (See alsoV.B.3.hhh.)

c. The fact that a specified NDEW could engage multiple targets byusing multiple beams from a single platform and hence is a highleverage system. (85-4)

d. The fact that an NDEW could have lethal ranges of thousands ofkilometers. (85-4)

e. The fact that a kill mechanism for an x-ray laser is ablative shock.(85-4)

4. Information concerning Directed Nuclear Energy Systems.

a. Generalized description of DNES principles, as well as generalqualitative or quantitative information on the physics andtechnology of low-power DNES research, that does notsubstantially: (86-1)

(1) Assist others in development of DNES weapons; or

(2) Contribute to feasibility assessment of DNES weapondevelopment; or

(3) Reveal programmatic directions.

b. General qualitative descriptions of DNES program goals orobjectives that do not reveal classified milestones orachievements or specific design characteristics. Classifiedmilestones and their achievements will be reviewed for release on acase-by-case basis. (86-1)

c. General studies of DNES special nuclear materials and theirphysical properties. Specific special nuclear materials whichare developed for (and the specific conditions of their associationwith) classified DNES projects and test device designs will remainclassified. (86-1)

d. General studies of other DNES materials and their physicalproperties. No material identities or associations will bedeclassified where such information may be used to infer classifiedDNES characteristics. (86-1)

e. General DNES computational techniques or analytical procedures.Computational techniques and procedures which utilize orreveal specific design or operational characteristics will remainclassified. (86-1)


1. Existing storage site.

a. Official names(s), nickname(s), and/or location, when associationwith the Armed Forces Special Weapons Project (AFSWP) or AECis not revealed. (53-1)

b. AEC storage sites (as pertains to all weapons in custody of AEC ata National Storage Site (NSS) and an Operational Storage Site(OSS)). (56-3)

c. Location

(1) When information does not explicitly reveal installation is astorage site for nuclear weapons. (56-3)

(2) DoD storage sites (as pertains to weapons in DoD custodyonly). With delivery organizations and operating forces inthe U.S. or overseas. (56-3)

(a) Fact that particular aircraft squadron, naval vessel, orspecial weapons organization has capability ofstoring or handling nuclear weapons. (56-3)

d. The approximate location of some of the national stockpile sitesand operational stockpile sites provided no indication is givenas to the total number of storage sites. (59-7)

2. Future storage sites

a. Official name(s), nickname(s), and/or location, when associationwith AFSWP or AEC is not revealed. Future storage sites becomeexisting storage sites at the time of administrative manning. (53-1)

3. Surveillance program. Mere existence of maintenance or surveillanceprogram. (53-1)

4. "In certain areas Soviet nuclear technology equals and in some areasevenexceeds that of the U.S., although our overall capability and means ofdelivery are believed to be superior to the Soviets." (62-1)

5. "The U.S. has a nuclear weapon in stockpile with a yield ofapproximately25 megatons." (62-4)

6. "The world was shocked by the 60 megaton test on October 30th. TheU.S. analysis has shown that this device used a lead jacket around thefusion materials, and gave only a few megatons fission. Thus the Russiansreduced the fallout, especially that which might have fallen on their owncountry. If lead were replaced by uranium, the Russian device would give100 megatons or slightly more." (62-4)

7. The identification of U.S. TX, XW, or Mark numbers with U.S. missilenames. (62-7)

8. "In order to achieve it, we maintain a total number of nuclear warheads,tactical as well as strategic, in the tens of thousands." (63-3)

9. The fact that we have deployed thousands of tactical nuclear weapons inEurope. (63-4)

a. The fact that the total kiloton yield of these weapons is wellin excess of ten thousand times the total yield of the nuclearweapons used at the end of World War II. (63-4)

10. "In presenting this proposal, it could be stated that 'severalthousand'nuclear weapons could be involved." This statement is contained in a U.S.Position paper on the Destruction of Nuclear Weapons to ObtainFissionable Materials for Transfer Under a Cutoff and Transfer Agreement.(65-3)

11. "The number of nuclear warheads in strategic alert forces has increasedfrom 850 on June 30, 1961 to 2700 estimated as of June 30, 1965."(65-5)

12. "The fact that U.S. strategic forces have an inventory of nuclearwarheadsin excess of 5,000, that the number of nuclear warheads furnished to theAlliance and stored in inventory in Western Europe has exceeded 5,000nuclear warheads, and that this number will increase by more than 20%during the next six months." (65-7)

13. The minimum spacing for specific nuclear weapons or nuclear componentsin storage or transit. (67-1)

14. Statements that qualitatively reveal that a nuclear weapon issatisfactory.(67-1)

15. Statements that quantitatively reveal specific component quality orreliability requirements. (67-1)

16. The fact that U.S. nuclear artillery shells are located in Germany.(73-6)

17. The estimated costs for the proposed improved nuclear artillery shellsas$452,000 each for the MK-74 (155mm) and $400,000 each for the MK-75(8 inch). (73-6)

18. The fact that any particular reactor product is being or has beenstockpiledfor military use. (73-8)

19. Information concerning the weapons stockpile: (81-1)
                                            Fiscal Year                                   1945    1946    1947    1948Number of non-nuclear components1. Gun-type                          0       0      (0)     (2)2. Implosion                         2       9     (29)    (53)Number of nuclear components3. Gun-type                          0       0       0       04. Implosion-type                    2       9      13      50Numbers in parentheses declassified in 1976.

20. Descriptions of historical and future trends in the total number ofnuclearweapons in, or megatonnage of, the total stockpile which are:

a. Qualitative. (82-1)

b. Expressed as a percentage change over any time period oron an unscaled graph with a scaled time axis for the past,present, or future up to and including the approved period ofthe current Nuclear Weapons Stockpile Memorandum(usually five fiscal years beyond the current fiscal year).(82-1)

Note: Remains classified if dramatic trendchanges result from significant unplanned eventssuch as major technical or production problems,sabotage, natural or man-made disasters, etc.

21. Descriptions of trends for any time period in nuclear weaponproduction or retirement rates which are qualitative, includingrelative comparisons of the production rate versus the retirementrate. (82-1)

22. The fact that the total nuclear weapons stockpile contains a fewtens of thousands of weapons (no numbers specified). (82-1)

23. The unelaborated fact of the presence of U.S. nuclear weapons in theU.K.(84-1)


1. The mere fact that the U.S. is interested in pursuing a program todetermine the characteristics of an "enhanced radiation" weapon (neutronbomb). (63-5)

2. The fact that we are interested in and are continuing studies on aweaponfor minimizing the emerging flux of neutrons and internal induced activity.(67-1)

3. The fact that the W-79 is an enhanced radiation weapon. (78-1)


1. The fact of weapon laboratory interest in MRR devices. (76-3)

2. The fact of successful development of MRR devices. (76-3)

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