V r Jt fij/ ,lEtCH[i: }ElLL\g( q.:;i. sub-;!sscmbiics and complcic aircraft, was one of the first to take an interest in ejection scats. The problems they faceil. and largely solved, and the they employed have been duplicated in some measure by all other ejection seal inanulacturcrs. Although the indi- vitlual characteristics of each scat are blanketed with patents, the operations ol all arc fundamentallv the Part I T HE PROi^LEM of how to sret the pilot out of a fast-mo\ ing aircraft existed even before the end of World War II, but it was only when jet aircraft began to in large means Jr go into service numbers that the problem became increasingly acute. It is signifi cant that in the ^8 operating manuals for or abandon- same. Martin-Baker first became interested in the dcN’elopment of an ejection seat during RM4. How to get a man weigh ing perhaps 200 Ihs. out of an aircraft travelling even at the fairly moderate S{x-ed of 400 knots problem to solve, especially no jirevious data to u'ork on and both’ had ever carried out such a ma- early types of jets, the drill f ing the aircraft and usually took the fo gested procedure”. The suggested cedure was to roll was invariably vague rm of a “sug- pro- over and attempt to fall out from an inverted position, a rather dubious proposition for the pilot of a fast aircraft was not a simple as there was .AmL. presumably aireaclv in difficulties. no- Nowadays, with the installation of ejection scats, the jxoccdtire for aban doning an noeiiver successfully. However, a few simj^le calculations proved that the energy required could not be provided by any arrangement of springs or other mechanical contri\’ances without an ex cessive weight penalty, and it was ob- '■lous almost from the outset that an explosive charge would be necessary to produce the desired result. Trial & Error; What type of jdosive to use, how to design a .scat to use it and. in particular, how to u.se it to achieve the desired result without injuring the occupant of the scat was a proiilcm that only long and patient experiment could solve. 16-foot rig was erected and a crude seal was built and attached in such a manner that it could he shot uj) the rig by vari- conihinations of explosives, while being photographed by a high-speed mo\’ie camera operating at 700 frames per second. The .seat was loaded with sandbags to simulate a weight of 2^50 Ills, at the time of ejection. Not onh were clifTereni types of propellant used, hut variations in the size of the ex pansion ciiambers and cartridge cases Were also investigated to ascertain the best combinations. From an analysis of the mo\ie film, estimates were made aircraft, far from being vague, is probably the most clearly defined and positive action that the pilot must memorize before taking the aircraft off the ground. There types of ejection manufacture of this particularly able are man^● in use. Thescatsji vaiu- picce of equipment has already become a highly competitive field. Basic Problems: The ejection seat de signer faces two fundamental problems. The first is to get the pilot out of the aircraft. The second is to ensure that he lands safely. That the problem has been largely solved in the case of the more conventional jet types i cx- test tESSSISS-' K IS proved by the number of successful ejections that take place every year, yet there i: litllc doubt that the advent of super sonic flight has in many instances again returned the drill for abandoning an aircraft to what is virtually a “sugge.sted procedure” with no IS ous guarantee of cess. It is generally assumed that a modern ejection scat will successfully carry the pilot clear of the suc- aircraft structure even at supersonic speeds. However, the successful completion of the operation is largely tlependcnl individual circumsiaces. Marlin-Baker Aircraft Co. Ltd.,* British firm which had jK-rience in the manufacture of aircraft on \ '' a ' Mtirliri-lialycr hus recently jormcil a (■inuuluni siihsitluiry which is cstahhshin^ n phnu at CtiUinpwoad, Ont. extensive cx- -A m /iiRCR.-irr of the various rates of aecelcratioii. iCvcniuaily the cxperiinerus were c(jii- tinned with live personnel. Using a sin gle cartridge the higli pressure at the be ginning of the stroke limited the ejec tion to about 15 feet. However, these experiments led to a number of impor tant developments. It was soon found that foot rests were required to reliexe pressure under the thighs from the weight of the legs. Unfortunately, one of the volunteer subjects of these experiments received injuries to his vertebrae, so that .Martin- Baker engineers arranged to sec oper ations being carried out hv surgeons on patients who had received similar in juries from other causes. .\s a result of the discussions it was decided that the initial acceleration was the cause of injury and the process would have to be reversed, i.e. the pressure should be built up slowly at hrst. rising to a maxi mum after a more gentle acceleration ha<-l. in e0ect, compressed the body of the scat occupant. This was achie\ed by the use of a two-cartridge arrange ment. .A. small charge initiated the ejec tion ami was followed immediately by the firing of a second and larger charge which completed the operation. This modification solved most of the basic problems and by the use of the two-cart ridge arrangement, it became possible for a person of normal jjhysique to make ascents of 70 feet up to a new and much larger test rig, without any apparent discomfort. These initial experiments confirmed one of the points which is basic to all successful ejection procedures, namely, that the vertebrae must be erect. If the head is bent downwards, or if the knees are too high, the spine will be curved I —4 F/igAr fholo Series of pieture.s on page opposite shows a low level ejection of a dummy from a CF-100. usin^ a Martin-Baker automatic seal. Below is shown S, L J. S. Fifield ejecliiijr from a Meteor whieli is still running along the runway; above, same ejection, with the main cliute developing, and M-B automatic seat falling away. \ ' . VvK,- ^ ● ■i- tj -K- ;iiui ihe inst;\!huion of llic scat iiilc [KTaiional aircraft, presented a contin- uinj: series of problems. ()iice the seal was ejected clear of the aircraft, it was recognized that some means of slowing it clown and stabiliz ing it was required. This was solved by the use of a drogue, carried iti a con tainer attached to the seal. When the seat left the aircraft, the drogue was released bv means of a static line. Tbe drogue prevented the seat from spin ning and enabled the pilot to free him self of the seat harness and fall clear to make a norma! descent. A development of this early design went into production as the MK. 1 scat and with it, manv successful ejections were made. It rapidh’ became a stand ard installation on virtually all high- s})eed aircraft in service in the R.^F. the Roval Navy and the Air Forces of manv other countries. In Canada, the seat was installed into the CF-100. For the past few years, incidentally, the Mk. 1 seal and its automatic successor, and other Martin-Raker equipment, lias been manufactured bv Canadian Flight F.quipment Ltd. under a license ar rangement which has recently been ter minated. SAFETY HARNESS SHOULDER STRAPS o NYLON —~ LOOP CALF STRAP SNUBBING UNITS D-RING PULLEY ASSEMBLYQUICK RELEASE- PIN later developments early scats found ready accejiiance, pro\id- ing as they did the first solu tion to the ejection problem, it was quite obvious that they were only the beginning. Even as the production lines were set up for the manufacture of the early type seals, experiments were being carried out to develop the idea further. A LTHOUGH the\ I)raMin}:^ illu>trat(> lavout and fimclioii of Martin-Bake'r Ralent Lep«- with fin>. Al U-fl i> a filled Ut liic; l>oii"las \-'t. c»r MMt is lill«Ml Ejection Seats By \nCHIE }ilLLAR or modilictl Iroin standard designs to suit specific aircraft. The aircraft manu facturer provides an “envelope'' — specification ami set of drawings of the section of the aircraft to which the seat will he fitted. Weber engineers then "tailor” the seat to fit the aircraft, en suring that it fulfills all the relevant specifications to the satisfaction of the customer. Multiplied Problems: For multi-seat aircraft, the requirements may vary widely, since it is sometimes necessary that the co-pilot be provided with a seat which can be rotated through 180 degrees from facing aft to facing for ward. This also involved an additional complication because the footrests, which are important parts of any elec tion seat, have to be retracted under the seat until imme*.liatelv before ejection. Weber seats must he bottomed before tiring ami this is accomplished by a ballistics actuator. The occupant lilts the left hand armrest to lock the inertia reel which anchors the scat h.irness. hand-grip is pulled, it locks the shoulder harness preparatory to ejec tion. The right hand-grip actuates a micro-switch on the canopy seal system, causing the canopy seal to deflate. It also tires the canopy remover. As the canopy leaves the aircraft, a lanyard from the canopy pulls the ejection seat catapult sear safety pin from the cata pult. thus “arming" the scat. The seat is fired bv squeezing the trigger inside the right-hand hand-gri[i. The propelling force is roughly com parable to that of a 37 mm shell. In almost all cases, U.S. seats are inte grated into the aircraft, i.e.. the mechan ism for jettisoning the canopy is linked with that for ejecting the seat. One of the largest independent L'.S. manufacturers of ejection seats is tiie Weber Aircraft Corporation which has produced a wide range of scats for the L'S.\F and USX. .\ll the scats are basically similar hut they dilTer greatly in detail. Weber seats are individually designed Part 2 N’ THE U.S.. a witlc variety of ejec tion seats are in use. many designed and produced by the manufacturer of the aircraft to which the seat is fitted, but some designed and built by special ist firms. An attempt has been made to standardize on some features and a specification. .\lIL-S-6326. lays down the basic requirements for seats used in USAF aircraft. I a The seat installed in Sabre Aircraft was originally designed by X'orth .-American Aviation Inc., and has proved be highly effective when circum- have made it necessary to eject to stances from these high-speed aircraft. .Al though the seat is actuated in substan tially the same manner as the .Martin- Baker scat, it differs considerably in detail. Xo face hliml is fitted, the seat being operated from rests ami a trigger luuler the right handles on the arm- hand-grip. Blow; When the leftto‘ccpacui: 33 May, 1956 neU. Lvfiuiuilly. ii uiKlcrwcni a series of eieciions Iroin llie Itomh bay of a fast hcimber. 'J'hc tests showed that ilie design had been siicccssfuh the fins maintaining the seat in a safe attitude wilhoui tumbling, until it slowed dowii and reached an altitude from which the pilot would be able to make a safe descent. Solution Vet: .‘Mthough the problem of supersonic ejection has not yet been fully solved, George Smith, a North American test pilot, abandoned an F- ]00 at Mach 1.0^. using a con\’entional tvpe seat and survived the ejection, although \\’ith fairly serious injuries. Smith's aircraft went into a dive at 3^.000 feet and reached 6,500 feet before he was able to gel out. The air craft has been estimated to have been travelling at 1.140 feet per minute or 777 miles per hour and the blast of air which hit him as he left the aircraft is estimated to have subjected him to a decelerative lorcc of 40 g's, equivalent to increasing his weight to 8.000 pounds. Althcugh Smith survived the experience, mainly owing to a singular of cO'incitlences which caused let series him to be [deked out of the ocean and rushed to hospital in a minimum lime, it is obvious that the seats presently in use for subsonic aircraft are inadequate protection against the forces imposed by ejection at supersonic speeds. This is H W ehor ejection ,«eat, fitted in many US.4F aircraft. A versi in the Mojave Desert (see I'chruary issue of Aircviif!. p. 39—Ed.). Future Developments: What of the future: It is probable that even in their present advanced state of development, ejection scats are only at the threshold of the real problems. High altitude flight is becoming commonplace and we may soon he entering outer space. Since aircrali are man-made creations and as such are always liable to failure, some provision must be made for abandoning them at very high speeds and extreme allitiules. Tlie one successful supersonic ejcc- linn aln-.ub made caused considet.ibic removes a safety pin. thus “arming” the seat, after a two second delav. The seat occupant can then, by squeezing a han dle inside the handgrip fire the catapult which ejects the seat. The seat is attached to the aircraft structure bv a second lanyard which, after a two second delay fires an initia tor which releases ballisiically the occu pant's lap belt and shoulder harness so that he falls clear of the seat to make a free parachute descent. The seat of course provides interior space for a survival kit and cushion and a l)ack-type i)arachutc. seats are provided with quick disconnect fillings ready for con nection during installation of the seal into the aircraft. Downward Ejection: Downward cjeciioti h.'is heeti tlu subject of a great (●.v[)eriinent:ilion. -Mlhougli ii the designer scat extensive open auto- AII W'eher I. deal of [xjse' ■O', pi ol iK 1 n- Inn..-Ir. I ●4 AlRCRAFr ‘injury to the seat occupant. Obviously some kirui ol shield is recpiircd to pro tect the occupant ol the seal from ilie airsiream when the seat leaves the air craft. There may also be increasingly im portant psychological problems. Super sonic flight within an enclosed ized and heated cock[)it produces very little physical sensation but little is known of the reactions of the pressur- average pilot once the canopy has been ejected. Some mechanical linkage whereby re lease of the canopy also ejects the seat— an c.xtension of the present interlocking system—may be indicated for single seat aircraft. Ejection through the canopy is also feasible, although the strength of the medern Ple.xiglas canopy makes this procedure hazardous. Since the feasi bility of downward ejection, e.xcept at low altitudes has already been de Picture .secpience shows Convair ro<'ket sled used to test F-IO-A ejection system: lop L, witli live rockets lirinjr, sled approuciies peak velocity: K, as sustainer rocket maintains slef sustainer roekel. Latter two pliotos were taken about .02.'5 see. apart. l.ower R. iiubariued from seat at trajeetory peak.Ejection Drill: Although a large number of highly skilled technicians are presently employed in improving [iresent devices for abandoning aircralt at the extremes of altitude, speed and acceleration, the human factor is still the one which poses the most [)roblems. In the U.S. it has been estimated that roughly 22° , of all seat ejections result in fatalities, yet the vast majority of these are ejections made at low speeds under comparitively mikl coiulitions. Experience proves that seat liesigners dummv il«>als down seromls aftor separatiny: X' . V'-,' ✓ Pictures above show «-lose-u[> of tbe sled as it is beiiitf rinidied for run down 10,000 ft. track at L’SAF Eilwards AI'IL Runs as fast as Mach. 0.9}{ have been made for installation of up to sixteen ro<-ket motors. (Coiitlniial on pii^c Provisi4ui ismade. 37 May. 1^56 construction of the tower h;ivc al ready heen received. In the interior, the DoT has awarded a confract to Daw.son Wade & Co. for the construction of a SI.200,000 airport, cast of W’illiams Lake. It is designed to handle the largest aircraft now on commercial operations. Ai the same lime, the .Vero Club of >P.C. is still petitioning the government to pro vide a light aircraft airport at Span ish Banks, also to be used as a sec ondary airport to Vancouver's Inter national Airport. At the j^resent time V^iiie Rock is under serious consid eration for this purpose. .\t hdmonton. an aerial survey of the new DoT airport near N’isku. 16 miles south of the city's centre on struclion work this winter, with the actual construction beginning with the spring of 1057, At Vbnnipeg, the construction of the new east-west runway at Steven son Field is continuing on schedule and the present north-south runwav has been extended anti strengthened to accommotlate heavier aircraft, in addition, the DoT has announced its intention to build a new $1,000,000 terminal building to accommodate the steadily increasing passenger and commercial traffic. north-six miles STARFIOHTER ' Coniimicil jrom page GO ) lacilities for which tenders peeled to be called within the two months. Also nearing completion is the aircralt taxiing and parking area in front of the adminis tration building. Work on the 400 )ard concrete strip was started last year. An additional $100.00(1 has been authorized by DoT for a 60 ft. are ex- mounted atop the swept vertical fin. Forced Down: The downward ejec tion seat is the first of its kind to be installed in a production jet fighter and the ejection sequence is of some interest. Lockheed says that to eject himself the pilot has only to pull a handle to start the following automatic chain of c\’ems: (a) the cockpit is depressurized and the stick pops forward out of the way; (b) the parachute shoulder harness snaps onto the pilot, his legs are pulled close .^10 to the bod)’ by “mechanical straps", and ankle clamjxs hoki the feet in place; (c) an explosive cartridge rclca.ses the escape hatch and jettisons the scat downward and outward; (’d) the jiilot’s seat belt unsnaps, freeing him from his seat, and at a pre-.set altitude the para chute opens. The dive brakes are located on the fuselage sides, back of the wing. drag parachute is installed under the fuse lage. near the end of the tailpipe. ●A large engine access door, on the bottom of the fuselage. ser\es a dual purpose. In addition to providing ready access to the engine, the door's inner panel holds most of the hydraulic equipment, to facilitate servicing. Dimensions are: span, 2] ft. 11 in.; length, 54 ft. 9 in.; height, 13 ft. 6 in. the Calgary highway, will commence early this spring according to Hon. George Prudham. Minister of Mines & Technical Survevs. The next new $600,000 sur\e)’ will co\er an area of some 16 square miles, with additional survevs of the administration and other buildinu sites and runways. The runways will be over 10.000 ft. in length. Tenders arc expected to be called for the mov able control lower. Tenders for the con- UTILITY UNLIMITED... EJECTION SEATS Now in service with the U. S. Marine Corps, the Kaman HOK-1 is shown here as a cargo carrier. An all ’round utility helicopter, it is equipped with a hydraulic hoist for rescue missions. Carrying litters internally, it doubles as an aerial ambu lance. Kaman is proud of the versatile role the HOK-1 is playing in our continu ing program of National Defense. f Conihitial from page 37)I K/UVIAf/ 4 have usually credited a man, acting under emergency conditions, with the ability to think and act faster than, in I ●< V THE KAMAN AIRCRAFT CORP., BLOOMFIELD, CONN. KAMAN AtRCRAFT Or CANADA, LTD. many instances, he is capable of ihink- htg and acting. WfOm Although efTorts to ‘IV- B improve methods S4 .AIRCRAFT tiixi-in::. Twin no',c; Li.sh- Tirc prcs-surcs arc ol: cscajK’ wi!! continue, ejection mu.sl always depend, in the final analysis, on the psychological actions of the airman. If, when the time to eject arrives he does not know the correct ejection precedurc, no techno logical features will be of avail. I'or this reason, a thorough understanding of the seat is absolutely essential. The user need not know the internal work ings of each component but it is essen tial that he should know exactly how to operate the scat and what effect his actions will produce. During World War II paratroopers found chat the [)rocess of bailing out could be reduced bv constant drilling to what was vir tually an instinctive reaction. There seems no reason why this lesson should not be applied to the ejection cirocedurc. i.e., that the aircrew' be drilled to eject virtually “without thinking” once the decision to abandon has been taken. In an emergency there is little time to beirin remembering a drill learned from a text-book. In the RCAF. text-hook instruction on emergency ejections is supplemented by training in a dummy cockpit fitteil with an ejection seat identical with the one which the pupil will be using. In this, all the necessary actions can be demon¬ whilepitching wheels arc used, with hydraulic straicd and the pupil can carry out the complete ilrill and [iroiluce the satnc effects as far as it is feasible to do so on the ground. successful post steering, palpably lower than Western practice. The flying controls do not appear to be power operated. The ailerons, which mounted on false spars, have sealed pressure balances and what look like large spring tabs. The rudder and eleva tor have unshrouded inset-hinge aero dynamic balances with rather small tabs —probably for trimming only. Fowler flaps are fitted between the ailerons and the undercarriage nacelles, and the engine nacelles, but not the fuselage. The power units type f.VI-109, prob ably single-spool axials) are the big question mark. The airplane is about the size of the Comet 3 and would he rc- TU-104 are (Cnnriiuicd fr/wi piif’c iO) and tailplane have 45'* deg. sweep, with a thickness/chord ratio of about 10°., thereby assuring a higher critical Mach number than that of the wing and consequently the maintaining of tail control even when the wing reaches its limiting conditions. Structures are of twin w'eb, torsion-box form with separate leading eilges. There is no sign of surface heating and the fin and rud der are rather roughly finished on this airplane. Highpockets: The landing gear is very tall, which makes it look slender. This characteristic is attributable to the fact that the gear is another Badger component am! since the Badger has a shoukler wing, long legs are a necessity. The main undercarriage has four-wheel bogies with front tension pistons to damp the the first shock of the rear wheels touching down, and to prevent expected to weigh about 150,000 lb. by Western standards. It may not, how ever. since Soviet economy usually pre fers prestige to payload, as witness the sparse seating used in the Aeroflot DC-5’s, Il-iTs and Il-15's. Yet when opcrateil by the satellites, these airliners carry normal loads. Impression of Size: The air intakes and powerplant bays arc big. Power is certainly about 15,000 lb. st. ih. and is probably derated from the bomber engines of 18.000 to 20,000 lb.'st./th. ●V>i A i*.vf .'** 9^ Criterion of efficiency 9^ — Every major development in the field of scientific filtration in aeronautics has found \'okes filters in close association with the , This has been the case ever since apioneers Yokes filter was chosen in 1934 as the first air filter ever to be fitted to a Service aircraft. Today most aircraft, and engine test beds, have Yokes filters specified — for fuel, air or lubricating oil; in this way the name of Yokes has become recognised as the standard ol filtration cfficiencv in the aeronautical world. PIONEERS OF SCIENTIFIC FILTRATION Rcpreiented throughout the worM VI99 YOKES (CANADA) LTD.. J80I DUNDAS STREET WEST. TORONTO 85 May, 1956

Ejection Seats - part 1

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AVRO Museum

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