The need to return to hydrogen in airships

By roaming around the RC Groups Forum I stumbled over a post called Fire & Hydrogen, interesting excert which linked to the first page of an AIAA Paper called "The need to return to hydrogen in airships", I have attached the first page for you to read to the bottom of this post. The paper was written by BREDT, M. of Buz Airship Co., New Orleans, LA for the 6th Lighter-Than-Air Systems Conference Norfolk, VA, June 26-28, 1985. This seems quite old but reading just this first page of the Paper it seems very interesting to me, the proposals made do not seem to far of. I would be interested to learn more about the concepts and Buz Airships, especially I would like to know more about what happened to the concepts and if anything came out of them. So this one goes out to you do you know more about this ? Or do you even know M. Bredt ? Let us know. Put a comment on the Blogpost or write in the Forum or post to our Mailinglist. What do you think about using hydrogen in airships? Can we now so many years after the Hindenburg disaster handle the dangers of hydrogen ? Considering hydrogen fuel cells are making their way into cars and the first planes is it time that the airship industry reconsiders hydrogen usage in one way or the other? Send us your feedback.

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as for AIRSHIP sealed double Drawing example, one p a t t e r n e d a f t e r t h e B Z U - a pressure and r i g i d d e s i g n having d i a p h r a g m - t y p e compartments and a wall outer h u l l . (See accompanying of t h e p r o f i l e of a i r s h i p . ) i n a gondola o u t s i d e of t h e main h u l l , i.e. The g o n d o l a i s t h e f l o o r i s a t ground l e v e l . made of a K e v l a r s k i n o v e r a Nomex honeycomb c o r e . The gondola i s f a s t e n e d d i r e c t l y t o t h e bulkhead s e a l e d diaphragm. The c e i l i n g o f t h e gondola i s a l s o made of a f i r e r e s i s t a n t honeycomb c o r e o f "Fire-Lam". I t e x t e n d s o u t beyond t h e e n t i r e p e r i m e t e r of t h e g o n d o l a (see figure). B e c a u s e of i t s h i g h p h y s i c a l p r o p e r t i e s i n a l l directions, i t is a l s o a s t r u c t u r a l part b e t w e e n t h e h e a v y gondola and t h e l i f t i n g hull. I t s exceedingly high f i r e r e t a r d a n t p r o p e r t i e s a c t a s an umbrella holding out hydrogen f l a m e s l o n g e n o u g h f o r them t o b u r n out. The g e n e r a l p r a c t i c e of a n a i r s h i p i s t o f l y a t about 2,000 f e e t above ground l e v e l . I f f i r e b r e a k s o u t a t t h a t level, the descent need n o t be d i s a s t r o u s . There i s time t o dump f u e l and cargo. I n t h e f i n a l c r a s h , remember t h e It w i l l s t r u c t u r e a c t s much l i k e a b a s k e t . b o u n c e o n i m p a c t and n o t d i s i n t e g r a t e l i k e a n a i r p l a n e . At t h i s p o i n t t h e f i r e w i l l b e o u t and t h e r e w i l l no f u e l t o s p r a y over t h e survivors The v e n t i l a t e d d o u b l e e n v e l o p e c u t s down o n s u p e r h e a t i n g o f t h e l i f t i n g g a s , which p r o v i d e s f o r l e s s e x p a n s i o n and t h e r e f o r e a l l o w s a h i g h e r l i f t i n g g a s volume, which i n t u r n o f f s e t s t h e a d d e d w e i g h t of t h e second envelope. at I 11 I 11~ . A i r e n t e r s t h e d o u b l e e n v e l o p e space A11 ( s e e f i g u r e ) a n d l e a v e s t h e r e a r a t A t m o s p h e r i c p r e s s u r e a t "A" s t a r t s a i r movement r e a r w a r d l y , a n d a s e c o n d a r y s l i g h t s u c t i o n f r o m t h e r e a r a x i s p r o p e l l e r removes i t t o t h e atmosphere. The r e a r a x i s main p r o p e l l e r should be powered by a n h y d r a u l i c m o t o r , whose p r i m a r y e n e r g y s o u r c e i s a hydrogen f u e l e d combustion e n g i n e i n t h e gondola, which i n t u r n a c t i v a t e s t h e h y d r a u l i c pump. T h i s system removes any lingering hydrogen between t h e h u l l s . The r e a r a x i s m o t o r h a s no h o t e x h a u s t p i p e s t o i g n i t e any t r a c e hydrogen. The diaphragms a r e o f K e v l a r a n d s e a l e d t o t h e i n n e r envelope ( s e e f i g u r e ) . They have f i r e r e t a r d a n t p r o p e r t i e s . . TECTION ,SYSTEM Because of t h e hazardous n a t u r e of h y d r o g e n , p r o v i s i o n s c a n b e made f o r a g a s d e t e c t i o n system s i m i l a r t o t h a t used w i t h t h e Space S h u t t l e e x t e r n a l t a n k . During f l i g h t a m a s s s p e c t r o m e t e r i n t h e p i l o t a r e a w i l l be used i n c o n j u n c t i o n w i t h " s n i f f e r " l i n e s v i a 114" t u b e s and a vacuum pump. The system w i l l s e n s e t h e p a r t s - p e r - m i l l i o n p r e s e n c e of Hz and 02. T h e s e l i n e s w i l l f a n o u t from t h e gondola t o a l l c r i t i c a l areas. I t t a k e s f o u r p e r c e n t oxygen i n t h e hydrogen t o become dangerous. The s y s t e m w i l l be a b l e t o d e t e c t oxygen i n t h e hydrogen c e l l s , and t h e e n t i r e arrangement w i l l w e i g h a l i t t l e o v e r one hundred pounds. * GONDOLA * One o f t h e d e s i g n f a u l t s o f t h e Hindenburg was t h e l o c a t i o n of t h e p a s s e n g e r area. The f l o o r was a b o u t t w e l v e f e e t above t h e lower p e r i m e t e r of t h e a i r s h i p ; a l o n g way t o jump i f y o u a r e n o t s i x t e e n y e a r s o l d . S e p a r a t i n g o n e s head and t h e hydrogen c e l l was o n l y a t h i n f a b r i c membrane. In this a r r a n g e m e n t , e v e n o n t h e g r o u n d , f i r e would g e t t o you q u i c k l y . I n a r e c e n t e x p e r i m e n t by Ciba-Geigy o n Nomax honeycomb p a n e l s c a l l e d "Fire-Lam", cube. t h e p a n e l s were assembled i n a n 8'x8'x8' I n s i d e w e r e aluminum c o t s w i t h b e d d i n g a n d clothes. I t was s a t u r a t e d w i t h n a p h t h a and lighted. The r e s u l t i n g f i r e m e l t e d t h e aluminum i n t h r e e m i n u t e s , and t h e t e m p e r a t u r e was r e g i s t e r e d a t 2000°F. However, i t took 1 4 t o 23 m i n u t e s t o b u r n t h r o u g h t h e p a n e l s . All you n e e d i s f i v e m i n u t e s f o r t h e hydrogen a i r s h i p t o burn o u t , and t h e p e o p l e a r e s a f e from f i r e burns. I weighed a sample of t h e s e p a n e l s , a n d i t came o u t t o 1 2 o z . p e r s q . f t . The e x t r a l i f t o f h y d r o g e n o v e r helium would more t h a n o f f s e t t h i s e x t r a w e i g h t . B e s i d e s , Nomex honeycomb i s a g r e a t i n s u l a t o r a g a i n s t A r c t i c c o l d and Amazon h e a t . * HELIUM - COSTS * I n t h e U.S., h e l i u m c a n be p l a c e d o n t h e job s i t e f o r a n a v e r a g e of $50.00 p e r thousand cu. f t . T h i s c o s t includes a short term l e a s e o n p r e s s u r i z e d c o n t a i n e r s . When t h e s e c o n t a i n e r s a r e t r u c k e d t o a U.S. p o r t , t h e n loaded o n a f r e i g h t e r and s e n t t o a n o t h e r c o n t i n e n t , and a g a i n r e l o a d e d on a t r u c k t o f i n a l destination, the cost i s staggering. A f t e r t h e tanks a r e used, they a r e shipped empty a t t h e same c o s t back t o Texas. I n many p l a c e s t h e t o t a l c o s t of helium, t a n k r e n t a l a n d f r e i g h t comes t o $500.00 p e r t h o u s a n d c u . f t . To f i l l a n a i r s h i p t h e s i z e o f a Goodyear b l i m p c o s t s $ 1 0 0 , 0 0 0 . 0 0 a n n u a l l y , because t h e r e i s a l s o a g r e a t d e a l of h e l i u m l o s s j u s t t h r o u g h t h e I n t h e B U Z AIRSHIP, t h e p a s s e n g e r quarters, a s well a s t h e crew, a r e c o n t a i n e d

Worldwide Helium demand

Bugra Moto from Skywork Media posted and interetsing question today at the Airshipworld Yahoogroup that I would like to pick up here to bring it to a broader audience, since I think it has probabaly been discussed widely in different lists and groups, but getting the conclusions, people have come to, is not so easy. Bugras point was the following:

Blimps & Airships with all these beautiful projects about heavy cargo lift, satellite communication, defense, floating giant hotel blimp etc.; which don't get me wrong I absolutely hope they will become full scale production some time in the very near future and I admire all of you out there who invest time, effort, energy and other resources in such projects; how will the ever increasing helium demand worldwide be met with only 2 helium manufacturing countries to my knowledge (being USA & Australia)...

And I don't mean to be pessimistic here. Just hope the supply will catch up to the quick increasing demand. Well sooner or later I know it will.

And this question is really an interesting one. What if Airships, are going to become easyly developable when their production costs become lower, how are we gonna have enough helium readily available? Will we need to consider hydrogen as a liftgas again just because helium is to expensive and to difficult to get? And, are the US and Australia not going to abuse their monopoly to drive costs, if the demand increases?
Please send us your Ideas and thoughts about this topic, on airship-list Colorado the discussion about hydrogen came up again and in feburary it was at the little blimps mailing list. We all agree that hydrogen is extremely difficut to deal with, but is it more dangerous then thousands of liter of kerosin fuel, todays airplanes are fueled with? Could there be an alternative, like artifical helium that is generated by some chemical process? Please share your thoughts about this topic with us.