India was a pioneer in mettalurgy.If the world wanted Zinc it had to only come to India once upon a time.

There is a furnace still in existance from the vedic period,in a place named zawar.Researchers have found the technique and have submitted reports.

Please go through this to know more : 

http://www.inae.org/metallurgy/News_pdf%20files/DH_07_08_07.pdf 

Now we shall move onto the Vaimanika shastra : 

There are 3 kinds of metals named somaka, soundaalika, and mourthwika. By mixing them, 16 kinds of heat-absorbing metals are produced.Metals which are light, and are suitable for producing aeroplanes are 16. They are heat absorbing, and should be used in the manufacture of aeroplanes.”.

There are detailed and very vivid descriptions of metals, their properties,their names,the alloy making etc.These metals names are in sanskrit.But the properties correspond to modern day aluminium say scientist who have done research in the vaimanika shastra. 

Their purification is done by methods of shodhanadhikara. 

The purification of Soundaala metal is like that of soma with regard to boiling in the cauldron, but the process of purification is with 6 acids, 7 oils, and 5 decoctions,Whose descriptions are given. We are not looking deep into these because they all are sanskrit names.Too much of it wil lcomplicate the note for the readers. If you would like to know more,Please drop your e mail id as a comment. 

They have numbered the metals that are used.Also they have indicated the metal number and that it belongs a particular group number.Thus they have had great classification techniques for metals. 

The ooshmapa metals are made up of three kinds. 

The heat-proof metals are made out of the three, Souma, Soundaala, and Morthweeka mentioned in the previous chapter. It is said in “Loha Ratnaakara” that each of the three yields varieties of seed metals.

By mixing. 

They mention of several different alloys and have described their properties.It reads the proportion in which each of them have to be mixed,the temperature specifications etc.I really wish we could decode all of this and some of my engineering studiying friends would come forward and try to build something out of the shastra. 

The fifth vareity in the second group.

According to “Nirnayaadhikaara”, the melting of the superior, medium, and inferior kinds of metals is to be done in 407 different kinds of crucibles. They are divided into 12 groups. For the melting of the root-metals the second group of crucibles is considered the best. 

Next the shastra talks about the place where the metals can be melted and so the plane’s body can be formed.

Then fire-place, number 9 in class 7 

Having dealt with crucible in the last sootra, we now consider the fire-place.

Experts mention 532 varieties of vyaasatikaas or fire-places. Of them Koorma-vyaasatika, or tortoise-shaped fire-place is best suited for melting the seed-metals for the Vimaana

Kunda-kalpa or the art of furnace construction mentions 532 kinds of furnaces. They are divided into seven classes, each including 76 varieties. Furnace no. 9 in the 7th class, is best suited for melting the requisite metals of the vimaana, and its name is koorma-vyaasatikaa, or tortoise-shaped furnace..

The bellows should be number 16 in the 8th class.

There are descriptions for this also.Those who are interested in knowing,please let me know so that  i can communicate to you. 

The next subsequent chapters deal with the MIRRORS AND LENSES,ELECTRICITY,MACHINARY and then subsequently move onto the CONSTRUCTION. 

Aryabhatta, bases all his suthras on a number system.One such number system ( something like an encryption system..) is what we have already seen ( Katapayathi sankhya) in earlier posts. 

We will have to understand this number system (aryabhateeya sankhya ) to understand his calculations.

in this number system… Sanskrit alphabets are numbered in the following manner. 

Ka- 1   Kha – 2     Ga – 3    Gha-4    Nga-5

Cha-6  Chcha-7 ……. So on and so forth with continuous numbering upto Ma-25 

Ya-30   Ra-40    La-50   Va-60   Sa-70  Sha-80 

E-100

U – 10,000

Ru-10,00,000 

Aryabhatta says in one of his suthras ” Bha upa kramo Grahaansha:” 

Upa Kramo Grahamsha: makes sense as to the degree of tilting of earth….but Bha has no meaning per say.If we refer the numbering system, Bha is of the number 24.

Thus, the tilting of earth is 24 degrees according to aryabhatta ,while the mordern calculation is 23.5 degrees. 

Now , we shall move onto our Vaimanika Shastra.

The Mirrors ! 

This chapter Deals with Seven Different types of mirrors to be used in aeronautics.

1) Vishwakriya Darpanam : 

Vishwakriyaa darpana is to be fixed on a revolving stand near the pilot so that he could observe whatever is happening outside on all sides.Its construction is also detailedly explained, the silvering and all technical processes are described, but the problem lies in deciphering the meaning of the sanskrit words of the ingredients. 

2)ShakthyaKarshana Darpanam 

As the vimaana flies through the regions of the sky, three classes of destructive forces tend to overcome it. This mirror is capable of neutralising and overcoming their effects.

The wind, solar rays, and fire are known as trivargas. Each of the three has evil effects on the plane’s pilot. Those evil forces this mirror will absorb and nullify.

3)Vyroopya Darpana 

When enemy planes with men intent on intercepting and destroying your vimaana attack you with all the means at their disposal, the viroopya-darpana will frighten them into retreat or render them unconscious and leave you free to destroy or rout them. The darpana, like a magician, will change the appearance of your vimaana into such frightening shapes that the attacker will be dismayed or paralysed. There are 27 such different shapes that are said to be possible. Sammohana-kriyaa-kaanda, or the work dealing with the methods causing insensibility, mentions 17 of them.

4)Kuntinee Darpanam 

We now consider the Kuntinee mirror. The wise say that the mirror by the glare of whose rays people’s minds get deranged is Kuntinee mirror. Paraankusha says that in the region of the solar electric heat waves of the sky, seven streams of poisonous whirl-winds derange the mind. the Kuntinee mirror acts as a protection against that evil effect.

5) Pinjula Darpana 

The conflicting inter-action of the solar rays is called pinjulaa. It has deleterious effect on the black eye-balls of the pilots. The pinjulaa mirror, by intervening will prevent the eye-balls being blinded by the evil rays.

It is said in “Amsubodhinee”, or the work on solar rays, “There are four directions, east, west, north and south, and four corner directions, south-east, south-west, north-east and north-west. The solar force of each direction has got its own intensity, owing to different fire-force, different seasonal force, the effect of the five winds, combined with the vaarunee or liquid force of the clouds, and the resulting tension gives rise to four evil forces, andha, andhakaara, pinjoosha, and taarapaa, whose glows, known as rakta, jaathara, taaraagra, and prabha, striking the eye-balls result in blindness of both eyes. 

6) Guha GArbaDarapanam 

The conflict between the electricity in the clouds, wind, and rays, generates forces harmful to pilots. The guhaa-garbha darpana, by attracting them and projecting them by electric force against enemy planes, renders the persons inside them physically disabled and incapable of figh.

7) Rowdree Darpana 

This mirror captures solar rays and concentrates them to a targetted enemy to liquify the same. 

By the mixing of roudree and solar rays an evil force called maarikaa is generated, and impelled by the solar electricity, it destroys the enemy planes.”