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