BIMAL K. SRIVASTAVA WhenWhen What happens when a huge lump of BlueBlue IceIce coloured ice falls from a clear sky? Falls From Well, there are Falls From conjectures, often magical Feature Article Feature TheThe SkySky!! explanations. But the culprits are often commercial aircraft. Read on to find out more.

This piece of blue ice is most likely from an aircraft flying over the International Air Route A791W Kolkata-Karachi on 6 October 1991 found near Mt Abu in Rajasthan (Photo Courtesy Prof. K.K. Sharma)

Suddenly, a big blast was heard as if Of course this was highly improbable, as N 19 February 2011, at around a bomb had gone off. Every one ran the weather was clear, there were no 09.30 hrs in the morning, a chunk outside only to find a clear sky and no clouds, and no thunder was heard. Could Oof green-coloured ice dropped clouds, thereby ruling out the possibility of the ice have fallen off from some flying from the sky in the Central Reserve Police a thunderstorm or lightning strike. And then object such as an aeroplane? Well, that Force (CRPF) Camp at Suthyana, Greater they saw it! A huge block of blue coloured appeared most likely. Noida near Delhi. The area on the ground ice weighing at least 10 kg that had where the ice fell also became green in created a hole about half a feet in the colour. The piece of ice was collected ground. Fortunately, no one was injured and the matter was reported by CRPF nor any property damaged. Photo of ice that fell in Imphal on officials to the Police. Scientists are still The big crowd that gathered to watch 31 January 2010 probing the matter. The only clue was that the phenomenon was at a loss to figure the area lies at a distance of about 40 km out how such a huge block of ice could to the east of the Indira Gandhi have dropped down from the clear skies. International in New Delhi and falls People took photographs from their in the approach path, where the aircraft mobile phones. Some wondered whether align themselves for landing. it was god’s curse. The ice block melted A similar incident occurred on 18 May after about two and a half hours. Many 2008 in a village of Haryana called Hajibas. people collected water samples from the Delhi and in its neighbouring state melting ice. And, as expected, the local Haryana are normally dry with no signs of Hindi newspaper reported the incident as the Monsoon during this period. The sky a mystic occurrence the next day. was clear and bright. The time was about Now, what could be the reason for 10:30 hrs in the morning. A marriage party such a bizarre event? Could the ice be a rested peacefully. collection of ice flakes or a bunch of hails? 19 SCIENCE REPORTER, JULY 2011 Feature Article

This is how the aircraft toilets are cleaned after landing of aircraft (above); After landing, the ground servicing vehicles clear the toilet tanks by removing the contents for disposal; (above right) Aircraft toilets look like normal toilets though they work on the vacuum suction principle (inset).

The Mystery water is the main carrier in home toilets All along the journey, the lavatory The most probable source of the blue ice carrying all the waste to the drains. waste is stored in a holding tank on the was indeed a commercial aircraft flying Unlike the toilets in household aircraft. After landing, the toilet cleaning high in the sky, and that too from the most bathrooms, toilets installed in modern carts are deployed by ground crew unexpected of places—from one of its commercial airliners work on the principle personnel who operate a valve to empty lavatories! of vacuum suction—active vacuum as the waste storage tank and make it ready Before getting deeper into the compared to passive siphons of household for the next part of the journey. It is physically mystery, let us see how the toilet system of toilets. Since the waste gets sucked out not possible for a pilot to dump a tank modern aeroplanes functions. In fact it is through vacuum suction, these aircraft while in flight. The exterior lever means only quite different than the toilet system toilets don’t rely on gravity and gush of the ground crew can operate the valve installed in our houses. water. that opens the tank while the plane is on The typical home toilet uses a tank When the aircraft toilet is flushed, it the ground. filled with water. When the toilet is flushed, opens a valve in the drain line, and the it starts a siphon that drains the contents. vacuum in the line sucks out the contents A chunk of ice that had fallen on the home of a US couple on 21 October 2006 (below); it damaged the bed The water then flows into the septic tank or into a tank. Use of vacuum requires very of the couple after crashing through the roof (bottom) in the drain system due to gravity. Thus, little water to clean the bowl (water may be replaced by the blue sanitizing liquid). Most vacuum systems flush with just two liters of fluid or less compared to six liters for a water-saving toilet and up to 20 liters for an older toilet. The use of vacuum system in aircraft offers two clear-cut benefits—reduced weight of the aircraft and saving of water (in fact this also indirectly results in reduction of weight of the aircraft). Because the vacuums are so powerful, the pipes can be made narrow and very little water is required for flushing. And since gravity is not involved, the drainpipes can be run straight up to the septic tanks to conserve space. They can also be made vertically up or down or in any other direction. Thus when a vacuum toilet is flushed, the solid waste and a The blue ice sample of 6 October 2009 after melting small amount of blue sanitizing liquid are turned into a blue liquid, like a sanitizing agent sucked into the tank. (Photo Courtesy Prof. K.K. Sharma) SCIENCE REPORTER, JULY 2011 20 Feature Article The United States Rare Case in Now, how do we co-relate the above- alone has recorded mentioned incident in a village of Haryana at least 27 incidents in 2008 with that of blue ice from an aircraft? Well, the location of the incident of blue ice impacts was compared vis-à-vis the routes followed by aircraft and phases of flight. between 1970 and Village Hajibas is situated near 2003, some of Pinangwan (Latitude 27053’37"N, Longitude 77007’30"E.), which is located in District. which caused Gurgaon (Haryana) at a distance of about considerable 75 km (aerial distance) from the Indira Gandhi International (IGI) Airport, Delhi damage. exactly towards south (on a bearing of 1800). This place lies below the Air Traffic Normally a dark blue coloured Services (ATS) route known as W-20N Aircraft Involved (Bhopal-Delhi Sector) and when over this chemical (sanitizing liquid) is mixed with Only passenger airliners are involved in such cleaning water inside the aircraft lavatory place, the aircraft are approximately 15 incidents due to the fact that only these to 20 minutes from land at IGI airport. This holding tanks to deodorize the waste and aircraft are equipped with heavy-duty to break down any solids. The blue route is normally used by aircraft arriving passenger toilets that are regularly used from the South (Bhopal, Nagpur, chemical serves another purpose. In the by passengers on board the aircraft. event of any leakage from the drainpipes, Hyderabad, or Chennai) and the distance Thus a defence aircraft or a small civil matches with the area where commercial the ground engineers are able to detect aircraft would not be involved in such the leakage by observing the presence of airliners are descending from their cruising incidents. level of about 30,000 feet down to 15,000 blue colour on the exterior of the aircraft In other words, one of the primary and thus repair it. feet, where temperatures are conditions for occurrence of such cases comparatively higher than the cruising is that the place of incident must be level. How the Problem Starts located below an established air-route or Combining all these facts and figures, Modern commercial aircraft cruise at high it should be close to an airport where the incident definitely deserved to be altitudes, and the sub-zero temperatures passenger airliners are operating. categorized as one of the rarest cause any liquid to freeze immediately, Another condition is that the ice will phenomena of blue aircraft ice falling to hence the term “blue Ice.” If any of this get formed during flight only when there is the ground. The matter was also reported “blue Ice” were to fall from an aircraft, it some kind of leakage or seepage in the to the Director General of Civil Aviation, would melt long before it hit the ground, aircraft toilets. This ice will however fall on New Delhi. It is understood from DGCA that dissipating into miniscule droplets that are the ground only under two conditions: though there had been many incidents of nearly invisible. i) When the airliner is descending (may leakage of toilet drains, this was the first In the event of any abnormality or be for the purpose of landing) so that the reported fall of blue ice in India. defect, such as due to leakage or atmospheric temperature outside starts seepage, small amounts of lavatory fluid rising, and the ice starts melting and falls Another incident of fall of blue ice in leak outside and get condensed due to down and/or; India was reported near Mount Abu in the low outside temperature. The outside ii) During cruise the ice lump becomes Rajasthan on 6 October 2009. A large lump air temperature at high altitudes may be too heavy (of the order of 50 to 100 kg or of blue ice weighing about 25 kg fell from as low as -300 C to -1500 C. Such low more) and ultimately falls on account of the sky in a farmhouse in Tokra Village near 0 0 temperatures turn the watery fluid into ice its own weight. Mount Abu (24 40’25" N, 72 42’40" E) at and with time more and more ice keeps Therefore, while analysing a case of around 0515 hrs, damaging some on accumulating over it. When the ice ice fall, the important aspect that is taken branches of trees. The pieces of ice becomes too heavy it gets detached and into consideration is whether the place of scattered all over the place. Once again falls to the ground. occurrence is either located on an it was taken as a mysterious case, since Normally this happens during the established air-route or close to it. If there there were no rains and the sky was clear descent when the aircraft encounters were two independent and separate paths with temperatures touching around 380 C higher atmospheric temperature on for incoming and outgoing aircraft at an in that area. The incident was witnessed coming from higher altitude to lower airport, the place would be located on by a 40-year-old Guard who had come altitude. The colour of such ice is normally the incoming path. In case the out to feed the cattle. blue (obviously due to the presence of blue aircraft is not found at the airport but on The case was examined by Dr. (Prof) sanitizing liquid). However, in certain cases an established air-route, this will show K.K. Sharma, Head of the Department of it could be green, blackish, yellow, muddy that the ice might have fallen due to its Geology at the Government College, or even grey. own weight during cruising. In such a Sirohi, who also consulted Jesus Martinez- A number of cases of blue ice falling condition, the weight of the falling ice Frias, a planetary geologist at the Centre down from commercial airliners have been should be very heavy, say about 50 kg or for Astrobiology in Madrid, and a pioneer reported in many countries. more. researcher of large-sized ice lumps. And 21 SCIENCE REPORTER, JULY 2011 Feature Article Incidents of Ice Fall in India

 Churu & Jhunjhnu areas of  Village Dauki, (UP) on 25 Rajasthan between October 2010 April 2008. Ice fell on the ground to December 2010. There were when the outside air temperature was three reported cases of fall of ice at 42°C. The place lies 14 km from Agra Village Dandu (20 km from Churu), Airport towards Southeast. It may be Village Sultana Ka Bas (Near possible that an aircraft approaching Jhunjhunu) and at Village Haripura to land might have dropped the ice. (Near Chidwa town of Jhunjhunu)  Village Belwari, Motigarpur between October to December 2010. (Dist. Sultanpur, UP) on 4 June The ice lumps weighed between 5 2007. A huge block of ice about 100 to 25 kg and were dirty or yellow in kg in weight fell on the ground and colour. The areas lie at about a broke into pieces. The place is located distance 250 to 300 km to the west 30 km away from Lucknow-Varanasi of IGI Airport, New Delhi on Air- route at 100 km from Varanasi Route G-450 from Europe to Delhi, about 40 to 50 kg. The place lies on towards Northwest. Reasons for fall and aircraft flying on that route the Mumbai-Goa Route (R461-S) at 265 of ice are not known. commence their descent at that km from Goa Airport towards  Village Ramnagar (Latori), Dist. point. Repetition of incidents Northwest. Surguja on 10 October 2010. Huge indicates high probability of ice being  Village Dorhatte, Shahganj, Agra blocks of ice fell in four fields (one detached from the passenger aircraft. (UP) on 29 October 2007. A block of was reported as weighing about 150  Mongshangei Maning Leika area ice about 15 kg in weight fell on the kg) and broke into pieces. The place in Imphal on 31 January 2010. A roof of a house breaking the roof and lies close to Air Route A791 (Karachi- block of ice about 5 kg in weight fell falling inside the house in Village Kolkata) where international flights down in Mongshangei Maning Leika Dorhatte, Shahganj, Agra (UP). The operate. Possibility of fall during cruise. area in Imphal breaking the roof and place is located just one kilometre  Village Sita Garhi, Mant, falling into the kitchen. It melted away from and it may be (UP) on 3 March 2008. into a blue coloured smelly liquid. possible that an aircraft approaching Place lies on the Agra-Delhi Route The place is located at a distance of to land at Agra Airport might have (L759-N) at 120 km from Delhi Airport only 1.5 km from , and dropped the ice lump. towards Southeast. thus most likely it was from an  Village Suryapura, Beruarbari,  Village Maheba (Dist. Orai, UP) aircraft landing there at that time. Ballia (UP) on 23 September 2008. on 7 February 2007. Ice block 10  Village Chhaman Ka Purwa, A smelling block of ice fell near a field kg in weight fell inside an enclosure Tikarmafi, Amethi (UP) on 13 in Village Suryapura near Surha Tal for sheltering animals in a village. February 2009. There was a case in Beruarbari (Dist. Ballia, UP). The The place lies at a distance of 90 km of fall of piece of green ice weighing place lies on Delhi-Lucknow-Patna from Khajuraho towards Northwest about 4 kg near a house in Village Air Route (A201) about 100 km from close to ATS Route W-33 (Delhi-Agra- Chhaman Ka Purwa, Tikarmafi, Patna Airport towards Northwest. The Khajuraho), where aircraft are Amethi (UP). This place is located ice might have been fallen from an descending for landing at Khajuraho. below the ATS Route R-460 aircraft approaching to land at Patna.  Village Dariyabad, Morna (Varanasi-Lucknow), at a distance of  Jashpur (Jharkhand) on 19 (Mujaffarnagar, UP) on 7 February 125 km from Lucknow towards August 2010. A 100 kg heavy ice 2007. A lump of Ice 10 kg in weight Southeast. lump fell here. The place lies on fell on a mango tree near a Shiv  Borana, Surendranagar (Gujarat) Kolkata-Kararchi route where Temple and broke its branches. The on 8 October 2010. There was a international aircraft cruise at high place lies on the Delhi-Dehradun Air case of fall of a piece of blue ice over altitude. Route 130 km from a house in Village Borana,  Village Padampur in towards Northeast. An aircraft Surendranagar (Gujarat) breaking the Kharsanwan (Jharkhand) on 15 descending to land at Dehradun roof of the house. The place lies 145 August 2010. A 30 kg heavy ice lump might be involved. km from Ahmedabad Airport on a fell here. The place lies at a distance  Lohat (Badli) in Haryana on 16 bearing of 233 Deg on Air route-W- of about 272 km from Kolkata airport, March 2011. A heavy lump of ice 50 63. International flights fly on this where aircraft are in cruising phase. kg in weight landed here, which is route to Ahmedabad.  Village Tiloi (Rai Bareilly, UP) on located just 21 km away from the  Village Tetvali (Dist. Ratnagiri, 13 September 2009. Village Tiloi (Rae Indira Gandhi International Airport. Maharashtra) on 3 October 2010. Bareilly), UP is located on the approach It is presumed that the ice must have There was a case of fall of piece of path on Air Route R-460 (Varanasi- got separated from an aircraft blue ice in Village Tetvali (Dist. Lucknow) at a distance of 70 km from descending to land at IGI Airport, Ratnagiri, Maharashtra) weighing Lucknow towards Southeast. Delhi. SCIENCE REPORTER, JULY 2011 22 Feature Article With so many possible cases of ice fall from passenger airliners, it is evident that such cases which were hitherto taken as “Rare of Rarest”, can The most probable source of the blue ice was indeed no longer be treated as a commercial aircraft flying high in the sky, and the rarest. that too from the most unexpected of places—from one of its lavatories! then, in consultation with Professors Dr. reported and investigated by FAA (Federal Megacryometeors Ritesh Purohit (Lecturer, Geology) and Dr. Aviation Administration, USA). It is true that not every piece of ice falling Sanjay Purohit (Lecturer, Biotechnology) On 28 November 2004 in Lynn (MA, from the sky is from aircraft. It could be from the same college, declared the ice USA) a huge chunk of ice fell on the house from other sources; it could also be a to have come from the lavatory of an of a lady that damaged the roof making weather related phenomenon. In scientific aircraft. a hole of 2 ft X 4 ft. smashing her jargon (mainly in Meteorological circles), It may be mentioned that Air Route bedroom floor. Aircraft Accident the phenomenon of abnormally large “A-791W (Westbound)” from Kolkata to Investigators from Federal Aviation chunks of ice falling from a clear sky is Karachi (which is an international air route) Administration were called to the lady’s known as “Megacryometeor”. The term passes through that area. Aircraft normally house who suspected that the ice might “Megacryometeors” however covers cruise at an altitude of 10 km or above have fallen from a low-flying jet heading various types of phenomenon of fall of ice over such air routes and atmospheric into Logan Airport. from the sky due to meteorological temperatures at that altitude are quite low Similarly, on 28 January 2007, a 50- reasons under unusual atmospheric (in the range of -300C to -1500C). So, the pound heavy ice fell on a Mustang car conditions. ice from aircraft at such high altitudes in USA damaging it totally. The above More than 50 megacryometeors would normally remain frozen unless and incident was also reported in the have been recorded since the year 2000. until it becomes abnormally heavy and prestigious New Scientist magazine of Analysis of megacryometeors shows that may drop because of its own weight. It is U.K. Some more events of this nature their composition matches normal rainwater for the areas in which they fell, therefore possible that an airliner cruising have been reported all over the world thereby categorising them as weather at a high altitude over the route might have from other countries. related. Thus, for all practical purposes, dropped the ice lump. In 2003, the HBO channel showed a the fall of “Blue Ice” from aircraft does not serial named “Six-feet-under” on this come under the purview of topic in which an ice chunk of the size of Reports from other Countries “Megacryometeors”. So, aircraft should be about one foot drops on an innocent The phenomenon of fall of ice from aircraft implicated only if other evidences also bystander. Similarly, in 1992 a Hollywood is extremely rare and normally may not be point to the possible role of an airliner. film named “Blue Ice” was also made on experienced at all. However, in USA With so many possible cases of ice such incidents, where Michael Caine’s between 1979 and 2003, a total of 27 fall from passenger airliners, it is evident character describes the concept of incidents of fall of aircraft lavatory ice were that such cases which were hitherto taken blue ice. A US TV show “MANswers” also as “Rare of Rarest”, can no longer be described the phenomenon. treated as the rarest. It is high time that the On 1 January 2005, the Federal airlines and regulatory authorities probe Aviation Agency (FAA), which is a deeper and take necessary preventive regulatory Government body for civil measures to combat cases of ice fall from aviation in USA, issued a fact sheet on the sky. the subject for the consumption of the general public, which clarified that not Mr Bimal K. Srivastava retired as General Manager, every strange looking and smelly object Authority of India. Address: G-11, Second found around their neighbourhood was Floor, Green Park Ext., New Delhi-110016; Email: from the lavatories of the airliners. [email protected], However, they advised the public to bring [email protected]; Website: http:// such matters to the notice of FAA for aerosurvey.in; Telefax: 011-41756621; Mob.: +91 further investigation. 98-106-04778 23 SCIENCE REPORTER, JULY 2011