In the earlier part of this report several features of on-board systems on which the pilot should be proficient were introduced. Yantradhikarana chapter forms the core content of ‘Vymanika Shastra’. Highly technical in-flight packages described in this part of the text comprise of nearly one half of the work. While highlighting the basic scientific research underlying the technologies, this topic adds substance to the belief that ancient India had a high level of scientific knowledge.

In this chapter relating to yantras, many mirrors, crystals or manis, naalas etc., feature as components of yantras. The text deals with details of on-board fitments, their constructional and operating methods, preparation process of special materials and the like. Before going into details, general points of observation are as follows:

  • What are referred to as 32 secrets and 31 special on-board packages (referred to as yantras) have no one-to-one relationship in terms of their serial mention.

    14 (verso). Shakuna Vimana:   Location of Yantras [Caption]

  • As it has been confirmed from several researchers on this work as well as similar works of ancient science, interpretations with reference to context plays a pivotal role in correct understanding. Virtually it forms a gate to make entry into disguised, coded and veiled textual contents. Once this barrier is crossed the rest seems to be relatively simpler. This need should be appreciated. A positive look notwithstanding, many scientists of modern school of thought may criticize this approach as ‘attaching meanings’.

  • Like in other parts of the text, there have been references to other works or principles of scientific subjects and technologies developed. The enormity of basic science behind development to evolve a variety of contrivances can be visualized. Quotations from experts in each discipline of science have been cited; showing the vast amount of knowledge that must have prevailed. It gives credence to the depth and profoundness of ‘Yantra Sarvasva’ to an extent that ‘Vymanika Shastra’ itself looks too innocuous.

  • Each system package seems to be conceived with compactness supplied with power source, using recycling process and modular in nature. From the manner in which it is explained in the text it is even possible that designs catered for using each system as a well conceived and need based entity. It could even be that selection of each on board yantra could have been based on mission role.

  • The locations of the yantras prescribed in the text seem to be apt and function related.

  • Many of the alloys and materials have organic and inorganic contents. This may look strange to metallurgists of modern science.

  • Each process of manufacturing of metals, alloys and Naalas gives:

    • a) Ingredients and their proportions of mix.

    • b) Use of specific-to-type crucibles.

    • c) Specific to type furnaces and bellows.

    • d) Specific melting or fusing temperatures on ancient scale. (kaksya)


  • Usage of a number of alloys, special materials indicate that they were definitely based on specific applications for which they were conceived and developed. Conceptualization and visualization of techniques must have logically prompted development of applied research.

  • The techniques that have followed concepts of application-specific systems developed to perform specific roles or functions were exclusively evolved for strategic and tactical roles, flight safety, communication and navigational needs. A variety of roles include photo reconnaissance, camouflaging, detection-avoidance, electronic warfare role, variable geometry, Biological warfare roles, remote sensing, evasion tactics, in air combat. In fact the applications seem to be more for use on aircraft in full-fledged military roles than for other purposes.

  • There is more than adequate substance in the concepts and techniques to substantiate that unless aircraft existed in those times and extensively used in various roles, development would not have been necessary or possible.

  • The term ‘enemy’ has been used in a generic sense with the interpretation that it denotes anything that can cause danger, harm or adversity. All these have been referred to as ‘enemy’. It could be the aircraft, ground or maritime forces of the opponents, it could be adverse environment, climate or space conditions, and it could be a biological weapon or any other adverse situation. Appropriate contextual interpretations in each case hold the key in meaningful deductions and understanding.

With these general observations we now go into discussions on the topic ‘Yantradhikarana’ or ‘Subsidiary yantras’. Efforts have been made to gather literature on research from other sources. The views of the study team are dovetailed in such cases. Whenever the discussion is exclusively from study team no reference is mentioned. In spite of constraints of time all efforts have been made to cover as many yantras as possible.

Before discussing various devices referred to as ‘Yantras’ in this chapter of the work, it is interesting to ponder over prevalence of yantras during earlier phases of Indian civilization. Dr. V. Raghavan, a former professor of Sanskrit in Madras university, has brought out a brief treatise, published by Indian Institute of Culture, Bangalore in 1956. In this booklet, the author has dealt with the subject in fair detail.

Starting from origin of the work Yantras from the root word ‘Yaan’ meaning ‘to control’, his narration starts form very rudimentary contrivances such as

  • Water pulley = Ghati Yantra

  • Oil presser = Taila Yantra

  • Cane presser = Ikshu yantra,

and goes on to more advanced devices such as those used for protection of fortresses, operation of fort gates, appliances used for bridge construction, weight lifting devices etc., His quotes refer to specific chapters and slokas from epics Ramayana, Mahabharata, Harivamsha, Buddist literature, Koutilyas’s Artha Shastra. Some of the yantras even relate to acquired technology from Persia. Valmiki Ramayana quotes use of several yantras in the fortifications of capital cities of Ayodhya and Lanka. They included devices to shoot arrows, stones at attacking enemy forces.

Among a variety of yantras, some interesting ones are auto-driven Rathas, water jet mechanisms for fire quenching, surgical instruments and strangely, some of the yantras seem to be for the purpose of torturing convicts. Contrivances used for battles included devices that hurled huge boulders at the enemy. He quotes some researches concluding that yantras with firearms and combustibles were widely employed in ancient Indian warfare. ‘Samarangana Sutradhara’ of Raja Bhoja is a unique work on this subject. To quote one of them mentioned by Dr. V. Raghavan, is the yantra ‘Parjanyaka’ a device which was used for causing artificial rain.

Many devices of architectural engineering applications include those developed for human pleasure, entertainment and the needs of the royal and the rich. What seems to be most amusing note is the use of ‘Robots’ employed for guarding security gates of palaces and mansions.

Dr. Raghavan’s discussions on yantras make very interesting reading. To top his treatment of the subject, it is appropriate to cite the ‘merits of good yantra or ‘machine’

The merits of a good machine, Yantra-gunas, are as follows:

  • Proper, proportionate utilization of the elements constituting it

  • Well-knit construction

  • Fineness of appearance

  • Inscrutability

  • Functional efficiency

  • Lightness

  • Freedom from noise where noise is not part of the scheme

  • A loud noise when noise is intended as an end

  • Freedom from looseness

  • Freedom from stiffness

  • Smooth and unhampered motion

  • Production of the intended effects (in cases where the ware is of the category of curios)

  • The securing of the rhythmic quality in motion (particularly in entertainment wares)

  • Going into action when required

  • Resumption of the still state when not required (chiefly in cases of the pieces for pastime)

  • Freedom from an uncouth appearance

  • Verisimilitude ( in the case of bodies intended to represent birds, animals, etc., )

  • Firmness

  • Softness

  • Durability

Note: The reader’s attention is brought to the comprehensive and fine details to which machine-design aspects could be perceived and structured.

With the above discussion on yantras brought in from Dr. V. Raghavan’s noted work, we resume discussion on more advanced and highly technical contraptions in the work of our study.

Vishwa kriya darshana darpana:

This is a photo device coupled with telescopic arrangement to obtain pictures from aerial reconnaissance of activities on ground. Essentially it is the photo reconnaissance role of the Vimana being talked about.

The interpretative skills of Sri M.K. Kawadkar on the analysis of the functioning and operative details his interpretation is attached as appendix.


The description of this device is mentioned as the first item under 31 parts of the Vimana for on-board use. Photoreconnaissance and Air surveillance are integral parts of air-warfare. Reproducing the function of this device from the work we read as follows ‘------ and enables the pilot to realize the conditions of the concerned region, and he can take appropriate steps to ward-off danger and inflict damages on the enemy’.

Analysis of the concept indicate that as the Vimana is engaged in offensive and defensive roles, the pilot is provided with the display of visual aid of the area around and take decision for defensive action as well as to assume attack mode. Tactical and strategic roles are thus covered. Employed possibly in reconnaissance role, pictures taken could be screened through photo-interpretation to decide the course of action and work out suitable plans.

Going through the constructional details, use of Vishwodara metal, crystals or glass beads, special mirrors for attracting solar rays, image reflectors, joint use of solar and electric power, mercury, universal reflecting mirrors, lenses together with actuating mechanisms have been discussed in the text. The end objective is to obtain ‘true-to-life’ pictures of the ground environment.

A careful examination of the expression ‘true-to-life’ pictures indicates that the pictures relayed to the pilot are not mere still photographs, but a continuous relay of all activities on the ground. Use of telescope and camera confirm this. Activities here should mean movement of troops, their strength, formation and deployment including their weaponry. In support of this interpretation it is necessary to closely observe the title of this device. Kriya meaning (activity) and not merely roopa or picture. It is logical to interpret as a continuous relay of all that is happening on the ground. In brief, use of cameras, telescopes, photo -chemical processes and the mechanisms of operating them are noticed.

Shaktyakarshana yantra:

One of the on-board features, this device is meant to neutralize and dissipate the effects of radiation occurring in the upper regions of the atmospheric frictions which generate dangerous forces. Severe forces are caused by winds and ethereal waves. This could be harmful to the structure of the Vimana. It is noticeable that this device is a flight protection contrivance against vagaries of dangers from atmospheric phenomenon. Constructional and functional details mention use of krowncha metal, special glasses, mirror made of Aadarsha glass, globular ball of Vaatapaa glass, liquefied mixture of load-stone, crystals, mica, serpent’s slough, mercury and crystals. The essential function is from six crystals or manis which are placed at specified dispositions. Further description explains that the influence of harmful forces and waves are absorbed through these crystals gradually and converted to heat before dissipating into the atmosphere. Rohinee Shakti and Bhadra Shakti are to be treated in a similar manner through a different arrangement in order to neutralize or mitigate the dangerous effects.

Here a study of upper atmospheric regions dealt with in Mc Grawhill series indicate that the eddy currents in higher regions are a potential danger to flying craft transiting through them.

Brief analysis of this yantra by Sri M.K. Kawadkar is appended separately along with Parivesha kriya yantra, Vistrutasya yantra, Vyrupya darpana, Padma chakra Mukha yantra, Kuntinee shakti yantra, Pushpini and Pinjuladarsha yantra, Nala panchaka etc., refer to appendix - G.

Angopasamhara yantra or folding up yantra at the seventh Bindu keelaka:

This yantra is basically a mechanical contraption installed for In-flight use. It is for protection of vulnerable parts of vimanas against intense heat. This heat is expected to develop under seasonal conditions. As the vimana is traversing with fully extended wings, Possibilities of exposure of some parts to this heat exists and this should be prevented. This relates to ‘sancocha’, a special feature provided for the pilot and features as Angopasamhara yantra.


It is essentially a protective device conceived for protection against overheating of the vimanas component while flying with fully extended wings. Here we also note the provision of variable geometry construction. When over heating takes place the pilot gets the feed-back of rising temperature. Depending on the requirements he selects and deploys the protective cover, shielding the parts from the heat.


We note here that temperature measuring device is also provided for relaying the data from the location to the pilot as his cabin display. Constructional and operating details explain use of metals Sumrileekas and Manjeera, probably in the form of thermo-couple device. Jacks and actuators to open or close the hatch are also mentioned. Pilot selects to operate only the required hatch depending upon the need.

For more analysis of this yantra Sri M.K. Kawadkar’s report is appended separately.

Guhagarbha yantra:

This refers to the special feature prescribed for on-board use in battle related vimanas.

The yantra called in full, as ‘Guhagarbha Aadarsha Yantra’ is to be located in the front bottom of the fuselage of the Vimana.

Its purpose is to detect presence of mines and explosives hidden by the enemy forces underground and transmit their pictures for the pilot’s display to know the location and shape of such destructive material. The end-use is to achieve precise location and defuse them in achieving safe passage for friendly ground forces. In this role the Vimana performs the function of tactical support to ground forces.

Constructional details of the yantra include use of different geometrical-shaped special mirrors in specified arrangement.

Through a sequence of reflecting mirrors, images/ pictures are captured and developed in-situ through chemical process. Special reflector called chumbakamani having a property of absorbing reflection from objects is used in the contraption. Solar rays and electric current are made to act on an acid vessel containing the crystal Chumbakamani. Electrified rays from the crystal are made to impinge on a downward facing mirror and this in turn will scan the ground underneath to take pictures of mines and explosives. The pictures are amplified and communicated to the pilot on a specially prepared screen.

The main constituents of the yantra are:

  • Fasteners made of Panchadhara loha

  • Wooden frame of Anjistha tree

  • Chumbakamani

  • Screen cloth coated with mirror-like gum

Details of fabricating include the following constituent parts:

  • Suranjeetaarsha mirror (72nd type)

  • Anjistaa tree

  • Paaragrandhika Drava

  • Chumbakamani

  • Pigments for coating the screen (to obtain clear picture)

  • Reflector or Virinchi varnish

  • Pathadarpana


  • The appropriate location of the yantra related to its function is to be noted.

  • Clear indication of use of concealed mines and explosives in battles of olden times. As a corollary knowledge of explosive materials and pyrotechnic devices should have evidently prevailed in advanced form.

  • Detection of such explosives through remote sensing gadgets had been envisaged.

  • Detection of underground objects through aerial remote sensing hints at use of special technology in the field.

  • The strategy in such detection hints at closely coordinated tactical air support roles to the ground forces.

  • The system indicates that technology existed in not merely detection of hidden explosives but also in defusing them.

  • Photographic and projection technique must have been in advanced stage of technology.

  • The surveillance role should be useful both in strategic and tactical role.

  • It is of interest to note that materials stated in this yantra have been developed by many science laboratories in the country. The materials are:

    • Chumbakamani (IIT, Bombay)

    • PanchadharaLoha, Paragranthika Drava (Birla science centre Hyderabad and Mumbai)

    • Reports from these labs have been appended to this report.


  • Multiple applications of crystals in digital technology are already seen in- modern times. It is no wonder if ancient scientists had employed this technology in a much wider sense.

Tamogarbha yantra:

Thamo yantra (darkness capturing device) is dealt with in fair detail in English translation of Vymanika Shastra.

The device is meant to protect vimana from poisonous fumes of Rouhinee or Kraakachaarimani rays projected by the enemy. This is in essence, achieved by creating a darkness around the Vimana to make it invisible to the enemy aircraft (ground forces as well) and make their target-sighting impossible. In this contraption Thamogarbha loha plays a key role.

The device works with revolving two faced mirrors collecting solar rays, activation of acid in the vessel on the opposite side, of mirrors, allowing solar ray to enter the crystal in an acid vessel. By turning a separate wheel in the west, darkness-intensifying mirror begin to function. By operation of a central wheel the rays attracted by the mirror will reach the crystal and envelop it. By operating the main wheel at high speed, darkness will envelop the entire Vimana making it invisible.

Preparation of the all-important Thamo garbha loha is as follows:

Black lead, Anjanika (collirium), Vajra Tunda ® In equal parts mixed and powdered® fish shaped Crucible® in crow shaped furnacre ®heated 100° or 354° C.


  • Concept clearly hints at a highly advanced concealing technique on the lines of stealth concept.

  • Visualization of such a need in air defense role in an attack mode is to be noted. It could also be a protection against similar offensive weaponry (biological & optical) in surface to air/air to air modes.

  • The technique somewhat resembles the creation of darkness (tama) using solar rays as seen in Dhwanta pramapaka yantra (refers to a research study on Anshubodhinee of Maharshi Bharadwaja Dr. Dongre's research, even though it discusses spectroscopic measurement.) In the three bands of solar radiation Tama (darkness) being the infrared band, if used for creating this darkness around the Vimana, the purpose of camouflaging is achieved in the same way. It is therefore interesting to study if the concepts are interrelated. Correlation of the two principles should be an interesting exercise.

  • Solar rays used in a big way here as well and hence there is every possibility of its direct derivation from Anshubodhinee.

  • It is appropriate to bifurcate, the sources of danger and their targets here. Poison gases targeted against aircrew and dangerous rays against both Vimana and aircrew . In either case Biological warfare concept is evident.

  • To note that the type of yantra prescribed here is one of the 132 types indicates vast ranges, basic research and development and much wider applications.

For more details on the above two yantras please refer to the analysis of Sri M.K. Kawadkar appended separately.

For the following yantras too, please refer the analysis of Sri M.K. Kawadkar appended separately.

  • Pancha vataskanda nala on the western centre

  • Rowdree mirror

  • Vataskanda keelaka at the bottom centre

  • Shakthistaana at the front and right sides

  • Shabdha-kendra-mukha at the left side

  • Vidyutdwadashaka at the north-east side

Shabdhakarshaka yantra:

This yantra is covered in a fairly descriptive style. This device is essentially a warning device to the pilot to get In-flight information on the presence of birds, quadrupeds and soldiers to facilitate taking deviation to safer routes during a mission. Broadly speaking the device is an audio sensor working on the principle of sensing audio waves within a range of twelve kroshas or 27 miles. Evidently its working is around the VHF range. It is significant to note that the Shabdhakarshaka yantra mentioned here is just one out of 32 varieties of devices developed under this category. This hints that other such devices for similar applications under other frequency bands from originators of sound sources had also been conceptualized and developed. Further from the description given the device appears to be basically a receiver-mode communication device.


  • It is understandable from the description that warning pickup signals in such cases should be from sources in short distance range (about 27 miles).

  • In case of warning by sensing sounds of birds it is a logical assumption that the warning needed is against bird concentrations. Birds do form a serious flight safety hazard as seen even today. Visualization of this concept as a flight safety requirement is to be noted.

  • Even if the ‘bird’ referred to is a ’flying machine’, advance warning of location of vimanas in numbers and the need for advanced warning would still be valid.

  • In respect of quadrupeds and soldiers talked about the interpretation seems to be to get a warning against cavalry and infantry forces largely used in battles of ancient times. Locating such concentrations through distant-sensing should enable a flying craft to opt for safer courses of flying. Such an option would be particularly useful for vimanas not capable of defending themselves.

  • Discussing the technical details, eight mechanisms constitute this interesting device.

  • Location of the device at the shoulder of the Vimana seems to be very aptly conceived from the point of view of good reception.

  • Use of a rotary system in the device with a pivot and rotating component to receive audio signals from all the directions adds credibility to the concept of an Omni directional audio receiver with hyper sensitivity.

  • Use of materials such as Rourava bird skin, metals specified for this technology, special dravas such as katana drava (acid), use of domes lined with birds skin (probably act as super sensors), ghantara metal, covering with kwanaka glass, capturing and processing sound inputs, amplifying them, use of rotating device for reception from all the eight directions, transmitting the terminal output to the pilot, all point to a well designed system developed for a well perceived purpose.

  • For the purpose of operating the system to capture sound waves, use of airflow to set in motion shabdhathene wheel has been mentioned. This will set in motion audio sensitive ghantara metal rod which in turn transmits to the dome lined with birds skin. Passing through simhasya tube and dronasya vessel amplification takes place.

  • Further description in the text includes methods of preparation of special metals forming the parts of the yantra

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