• NOTAR design • Multi-role helicopter • Police patrol
The basic design of helicopters has changed remarkably little since the first practical machines flew in the 1940s. But McDonnell Douglas has taken a giant step in making rotary-winged flight both safer and quieter with its revolutionary NOTAR, or ‘no tail rotor’ concept. It was first used in the MD 520N and is now seen on the advanced composite construction Explorer. The NOTAR can even be reversed into trees or water and will still remain functioning.
▼ Police squad
Law enforcement agencies operate the MD 520N with great success, with the low noise emitted by tho NOTAR system bong a great advantage.
A Rescue
NOTAR is useful for sea rescue missions, as it con oporato oven when immersed in water. Emergency floats can be fitted as optional extras for ovor-watcr operations.
FACTS AND FIGURES
McDonnell Douglas ostimatos a worldwide demand for up to 1,000 NOTAR machines in the dec ado to 2005.
Tho first NOTAR was declared ready after over 1,000 hours of tost flying.
By 1993 over 100 operators had taken out options on over 250 MD Explorers.
In September 1993, an MD 520N flew the 215-km (130-mllo) trip from Paris to London in a class record of 1 hour 22 minutes and 29
seconds
► The first user of a NOTAR helicopter was the Phoenix Polico Department. Arizona.
|
|
 |
|
Tjfpe: e-gftt-seat ovii hei-copter
|
|
 |
|
1995 have Іхчгп sold to point* departments and other law cnfotiement agencies McDonnell DtHiglas has also launched an advanced new NOTAK light-utility helicopter called tlu* l! xplofer Made largely from carlxm fibre and composites, it first flew in 1992
|
|
|
Military interest in the NOTAR system remains limited. However, the US Army conducted experiments with the concept tor special operations, whore its low noise was a useful asset.
|
|
|
|
|
The McDonnell Douglas Helicopters 520N is now in use with several private operators and polico I or cos, and has provon tho superiority of Ом» NOTAR concept.
|
|
|
|
|
|
|
The ethexm Uio** of the E. p&x»* дієм * • rxgn cium «peed the иск ot ■ led rotor aho I «чр» toreduce drag and wnsiod energy, ax orrti-torque tore* « produced by Hie ftn in the cruse
|
|
|
The rnsn rotor system is U ccowrocma: v. v CiOurl rotor with ocnootato hock» які ші ■rftaiilitxj hngoU rotor hivkl
|
|
 |
 |
|
fiisroago. botow tho twfeoom the is to «void rtortontneo of the hoi eng no дам» wAh the NOTAR dud
|
|
|
Vet another advantage ot NOTAR is tnar tte taftcom e sagfttty shorter than n u conventional hetcopter.
The makes <t eeser to manoointe the arorott m contmod spaces Tho boom can even bo mvaaod «to Модо Atth саго
|
|
|
The Гідг т ccr^rcts ot a NOTAR lieiKopter ore ОапіслІ io triouo of a conventional tat rotor oat Trj; onr mom afforonai» mot the yaw BgjW ‘r-vn :iv> Otolfe pedals » even того Cm© nr і ",;norrar. e than usual
|
|
|
The MD 520 totams a conventional ■ skid undercarriage smuar to щ гміапі anceeicr. tno Hughes 600 tt s constructed d ьтое аюу tubrq,
|
|
|
|
|
How NOTAR works
ThE C0ANQA EFFECT: N0TAR works by Ok’ Coanda effect. This is tho – air flowing over a curved area
the path of that Surface. W. th tho ‘•JlAR concept ttie trri rotor bocm n tho surface. rgoTAR uses a (an to Ы pressure ar and и sieevo to control the,-»rtVow arcxnd the tatboom Tie
|
|
|
ROTATING SLEEVE. Tho air bloods out through one side of a rotating sSeeve. tt then follows tho profile of tho tartboom. drawing more ot trie main rotor downwaah over the slotted side than the unstotted side This generates a force towards which opposes the rotor torque force.
TAIL CONE: Vaw control <s gooeraicd try tho rotating tsA cone, wheft nfeasos того at from the fan This acts as a simpto dreef /cl. and does not roly on tfie Coanda «iffnet In forward tight, most Ы the anti- torquo is produced by the tal ftns.
|
|
|
Ifte МОГЛА »r»rtm remove» a major cam of rone, me еяНгсітд jirfbw between • UU rolor and in* man rceor. Ih* EC-135 he a Un-rvhn. pr tarowon. to Into reduce ttvs none
|
|
|
|
|
|
 |
|
|
Mil
