Sunt masinile mici sigure?... Nu chiar...

Imi amintesc ca in Martie, inaintea deschiderii unui salon auto, am avut o discutie oarecum contradictorie cu unul dintre managerii Ford Canada.
Eu sustineam ca desi au totusi elemente de siguranta pasiva, masinile mici nu sunt chiar atat de sigure intrucat masa joaca un rol extrem de important intr-un accident. In contradictoriu, el sustinea ca vremurile cand "mare inseamna sigur" s-au dus si ca in ziua de astazi o masina oricat de sifonata ar iesi dintr-un asemenea accident, ocupantii sunt protejati.
Este adevarat, masinile de astazi au o siguranta pasive net superioara celor din trecut si sunt construite avand la baza tehnologii menite sa inlature pe cat posibil pericolul: motorul este in asa fel amplasat incat sa fie impins sub habitaclu, nervuri bine gandite menite sa absoarba pe cat posibil orice forma de impact, design special facut sa aibe o deformare controlata si sa directioneze materialul in exterior, structura "cusca", elemente de protectie laterala incluse in usi, etc.

Cu toate acestea, in conformitate cu legile fizicii, consider ca masa are si va avea in permanenta un cuvant de spus.

Astazi, am gasit pe yahoo un articol interesant care sustine aceeasi teorie pe care si eu la randul meu o imbratisez. Imi cer scuze celor care nu stiu engleza.
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Small cars won't keep you safe

Forbes.com - Hannah Elliott


While environmentalists push laws requiring automakers to sell smaller, lighter cars in order to meet higher fuel-economy standards, safety advocates worry that meeting those demands will result in cars that are less safe in a crash.

They might be right. A report released today by the Insurance Institute for Highway Safety (IIHS) praises President Obama's plan to boost fuel economy standards for cars by using a size-based system that removes incentives for automakers to manufacture only tiny cars. The report also says mid-size and large sedans must have a place on the nation's highways because--even with airbags, electronic stability control and strong front-crash ratings--small cars are much more dangerous in head-on crashes than larger vehicles.

'A really, really poorly designed or insufficiently designed large- or medium-sized car may be more or less protective than the best-designed small car, but that's something that you're not going to be able to tell just by looking at crash-test ratings,' says David Zuby, senior vice president of vehicle research for IIHS. 'So all things being equal, if you're concerned about safety, you want a bigger, heavier car.'

The statistics support Zuby's claim. Death rates in minicars involved in multi-car crashes are nearly twice as high as those in large sedans, according to IIHS data. In single-car crashes, 11 people per million were killed in large sedans in 2007, compared with 35 per million killed in small cars. In mid-size cars, the death rate for single-vehicle crashes is 17 per cent less than for minicars.

The new report is especially noteworthy because normally the National Highway Traffic Safety Administration (NHTSA) crash tests are performed using a stationary wall and a single car--not two cars being crashed into each other.



The Laws of Physics

The Arlington, Va.-based IIHS rated front-to-front crash tests between microcars and mid-size sedans. The Institute chose 2009 models of the Honda Fit and Accord, the Smart Fortwo and Mercedes C-Class, and the Toyota Camry and Yaris. It did not survey SUVs or large sedans in order to show how much influence even small increases in size and weight have on crashes, the report said.

Vehicles from Daimler, Honda and Toyota earned study slots because they have small models with 'good' ratings--the highest that the IIHS awards--in a 40-mile-per-hour frontal (stationary barrier) crash. But the Fit, Fortwo and Yaris performed poorly in frontal collisions with midsize cars, according to the new report.

Size is important because mass, coupled with acceleration, determines the force of a crash. Injuries depend on the forces that act on the occupants in the car, not on how much external damage the car sustains. The force of a crash turns on two key attributes: the weight of the crashing vehicle, which determines how much speed must be absorbed during the impact, and the size of the vehicle, which often determines how close the front of the vehicle is to the driver--an essential indicator of the extent of injuries to the legs and torso.

'When we run our crash tests, we see that the vehicles that crush up more when we crash them are ones in which the forces on the dummies inside ... are much higher,' Zuby says. In other words, the occupants of the smaller car are at greater risk of injury.

In the crash test between the C-Class and Fortwo, for example, the Smart bounced off the C-Class and turned 450 degrees before landing and displacing the instrument panel and steering wheel through the cockpit. The C-Class had almost no intrusion of the front gears into the passenger area.

Granted, the IIHS tests are much more severe than government safety standards mandate, as small-car proponents often note. The Smart Fortwo meets all U.S. government crash-test standards, including a five-star side-crash rating, notes Dave Schembri, the president of Smart USA. It also earned the highest scores for front- and side-crash worthiness from the IIHS itself.

'People drive small cars for many reasons, not just fuel economy as the IIHS states,' Schembri said in a written response to the report. 'People choose small vehicles because they are generally more environmentally friendly, a great value, they provide for greater driving and parking options in congested urban areas, and many consumers tell us they are simply more fun to drive.'

The IIHS report also notes that advanced crash-avoidance and crash-protection safety systems, like the electronic stability program and a reinforced steel safety cage found in the Smart, do help mitigate crash results.

Honda's Fit fared slightly better in its crash with the Accord (the Fit is the safest minicar sold in the U.S., according to IIHS safety ratings), but the dummy's head struck the steering wheel through the airbag, and Institute testers recorded a 'high risk of leg injury in a real-world crash of similar severity.'

A written statement from Honda in response to this report said Honda has specifically addressed frontal crash compatibility between vehicles of different size and ride heights. It has done so by developing a body structure placed in all 2009 vehicles that helps absorb the energy of a frontal crash by channeling energy through both the upper and lower structural elements.

The statement also pointed out that the IIHS tests are under 'unusual and extreme conditions' conducted 'at higher speeds than most real-world vehicle-to-vehicle crashes.'

The Yaris, in its crash with the Camry, lost a door and, despite the airbag, also forced the dummy's head against the steering wheel. Excessive head and neck injuries, plus deep gashes on the right knee of the dummy, were also reported.

Brian Lyons, the safety and quality communications manager for Toyota, says the real question for a 'comprehensive safety assessment' is how well the vehicle's safety systems perform in real-world accidents. According to NHTSA data, he says, less than 0.06 per cent of all frontal crashes occur at the crash severity selected by the IIHS.

'The IIHS test is equivalent to an 80-mph closing speed (with opposing vehicles traveling at 40 mph), a speed and energy higher than 99.1 per cent of all real-world crashes,' Lyons said in a written response to this report. 'According to NHTSA, vehicle safety in all car classes continues to improve, in part due to the active and passive safety features developed by the automotive industry.'



A Happy Medium

Minicars have many admirable qualities: they're affordable, they use small amounts of gas, they emit less carbon and they're easy to park. But if you're concerned about safety, there are other ways to save gas than buy a Smart Fortwo, says Christie Hyde, a spokeswoman for AAA.

Hybrid technology and turbochargers, which enable smaller engines to produce more power, can help larger cars run just as efficiently as smaller ones, she says.

'There are definitely a lot more options' than buying a Smart, Hyde says. The $14,500 coupe gets 14.03 km per litre in the city and 17.43 km per litre on the highway.

The $17,130 Hyundai Elantra (10.20 km per litre city/14.03 km per litre highway) and $16,130 Suzuki SX4 (29.35 km per litre city/12.33 km per litre), not to mention the $35,385 Acura TSX (8.93 km per litre city/12.75 lm per litre highway) and $31,822 Chevrolet Malibu hybrid (11.05 km per litre city/14.45 km per litre highway), all offer generous gas mileage coupled with a four-door sedan body.

Choices do abound, and no one car is right for everyone, Zuby concedes. But there are enough, he says, that deliver on fuel-efficiency as well as safety.

SURSA: yahoo.ca
http://ca.autos.yahoo.com/p/1368/small-car...t-keep-you-safe

This post has been edited by Rebel: May 10 2009, 07:41 PM

Pai si de ce e subiect de combat asta??

Astia de la Forbes nu i-as citi nici pe buda, asa ca hai sa-i lasam.
Suna complicat da in capul meu e simplu. Daca toate masinile de pe strada sint mici, masinile mici sint foarte sigure. In traficul de azi, unde sint tot felul de Q7 si Suburban pe strada, depinde enorm de tipul de impact. La unele ai siguranta activa, la altele pasiva, daca dai in zid e altfel etc. Asa ca te uiti la statisticile cu mortii in accidente pe masina. Ca alea cumuleaza toate situatiile. Acum 2-3 ani statisticile astea erau dominate de SUVuri, in general americane. Acum sint si SUVuri foarte sigure, ca de exemplu X5, dar mi se pare clar ca masa nu e asa importanta. E importanta intr-un anume tip de accident, dar nu pe total.

1. Eu merg pe ideea ca nu poti avea 2 accidente identice decat daca le simulezi deci pregatesti conditiile de impact
2. Noi in familie am avut parte de un accident din asta, small car vs. big thing(autocar adica) si soferul a avut noroc cu carul
3. De bine, de rau, mai toate masinile de oras din ziua de azi au 4-5 stele la testele Euro N Cap, care chiar daca nu-ti salveaza viata de fiecare data, amelioreaza urmarile. Fieru ca fieru dar omul il faci mai greu la loc
4. Eram cu tata in Tico odata cand a facut stanga fara sa se asigure si venea tramvaiul, nu a luat decat un colt de masina. Era clar atunci ca daca era o masina normala ori se oprea ori erau pagubele mai mici.
5. Mama are un C3, care, ma gandesc eu, e ranforsat un pic peste medie pentru ca e al naibii de greu 1100kg, varianta cea mai cheala(si optiuni si motorizare)
6. Hai ca pun niste poze! Aveti aici un exemplu de small car vs. big thing

In care din aceste 2 masini ati vrea sa fiti in caz de Doamne Fereste?? In cea de 5 stele (http://www.euroncap.com/tests/fiat_500_2007/298.aspx) sau in cea de 4 stele (http://www.euroncap.com/tests/audi_q7_2006/262.aspx)

Asta e un caz f probabil pe la noi... la cate Q7 am vazut si la modul in care sunt conduse..
Dar bottom line, as prefera ceva de talia LandCruizer din cauza berbecilor de pe sosele.

Poate il muta Mike la masini.ro ca eu nu am reusit.

Nu stiu cum sa zic dar eu am o oarecare reticenta la masinile astea mici. Masele joaca un rol enorm in impact. Si la mine in casa s-a adus discutia despre un Smart, " ca este asa de mic si de dragut", si am zis NU.

Mie (eu fiind supravietuitorul din pozele lui Mike) Tico imi dadea un sentiment de siguranta din cauza faptului ca puteam sa evit accidentele. Chiar s-a intamplat de vreo cateva ori sa ma feresc de niste tamponari in mod miraculos.

La clipul pus de Horia lipseste analiza de dupa impact. In testele de la Fifth Gear partea ce mai interesanta este inspectia ulterioara, cand ne arata daca se mai deschide usa, sau macar e la locul ei, ce s-a intamplat cu bordul si alte detalii d-astea.

Eu la Smart fortwo sunt multumit ca la testul EuroNCAP ramane usa intacta. L-am vazut insa intr-un test in care s-a rasturnat fiind aruncata cativa metri. Atunci avem o problema.

Edit: vad ca la Fiat500 avanseaza bordul destul de mult in faza finala a impactului. Asta e ingrijorator.

This post has been edited by Diesel: May 10 2009, 10:12 PM

Diesel, ai dreptate. Dar cand un mare procent dintre participantii la trafic conduc truck-uri si SUV-uri... atunci avem o problema...

Pai depinde cum definim siguranta asta.

In cazul unui impact cu un obstacol, stelele NCAP au o oarecare semnificatie, am putea spune ca masinile mici sunt cel putin la fel de sigure ca cele grele. Conteaza cat de bine sunt facute, nu cat de grele.

In cazul unui impact masina-masina, masa e f importanta. Pe siteul NCAP e un articol (tras de par, l-am citit destul de atent ca sa ma prind cum l-au tras de par) care face o referinta la un alt articol in care se spune ca fiecare 100kg in plus scade in medie cu 7% probabilitatea unei vatamari grave. Pare rezonabil.
Daca lovesti bot in bot o masina de 800kile si una de 2.4t, la 60km/h, asta echivaleaza cu un impact la 30km/h pentru aia grea si 90km/h pentru aia usoara.....Chiar daca aia grea are doua stele si aia usoara are 5 as prefera sa fiu in aia grea.


Pe de alta parte, putem gandi si din alt unghi cand discutam de siguranta unei masini. Daca tu esti intr-o masina medie, un VW Golf sa zicem, si intra un betivan in tine, ati prefera ca betivul sa fie intr-un Q7 sau intr-un fiat 500? Mie din acest punct de vedere masinile usoare mi se par mult mai sigure....

De acord cu tine. Pana la urma orice masina este o grama de fiare gandita, cel putin teoretic, sa se deformeze intr-un anumit fel in cazul unui impact pana la o anumita viteza. Nu as paria in cazul unui accident pe o masina mica, fie ca vorbin de un Smart Fotwo care are o structura extrem de rezistenta dar care iti face organele interne praf (pentru ca o mare parte din fortele impactului nu sunt amortizate de caroserie) si nici pe Fiat 500 care desi se deformeaza bine daca il lovesti de un zid, Doamne fereste sa te loveasca un SUV. Legile fizicii sunt peste orice test de laborator.
Din cate stiu cele mai riguroase teste de siguranta le are Volvo. Are cel mai performant centru de acest gen din lume si atunci cand proiecteaza un model analizeaza cateva mii de teste reale. In privinta asta nu am mai auzit sa mai procedeze cineva asa

Honda mai are un centru de testare de genul asta, integrat intr-un centru cu mai multe facilitati, la Tochigi.
Fac crash teste intre masini din diverse clase si incerca sa obtina o cat mai mare eficienta

This post has been edited by DRAGOS: May 11 2009, 01:09 PM

cam asa ceva are si Volvo, numai ca platforma respectiva se si misca astfel ca se pot face teste de impact din mai toate unghiurile posibile si la viteze diferite. Cand ajung acasa o sa postez linkul de pe youtube cu simulatorul respectiv (la serviciu avem accesul pe youtube.com restrictionat )

James, asta-i cea mai tare definitie.
Dau o bere virtuala.

in drumul meu de la serviciu spre casa, autostrada pe care am de mers coboara vertiginos vreo mila si jumatate, si exact la baza dealului se despart 3 benzi pentru intrarea pe alta autostrada. imediat ce ai intrat pe cealalta, pe la ora 6-7 seara ai un soare care iti bate exact in ochi, asa ca viteza pe celalata autostrada e cam cea pe care o are fiu-meu, cu 3 saptamini de experienta de umblat in picioare. dar ideea e ca cele 3 benzi care se despart merg foarte incet, pe cind celelate merg de obicei la 70+ mph. imaginati-va ca e o diferenta de vreo 40-50mph intre doua benzi adiacente, eu sint aproape oprit intr-o honda care ajunge pina la jumatatea rotii unui camion, iar pe linga mine vuiesc tiruri ale caror frine din cind in cind se mai si strica, sau care mai incearca din cind in cind sa evite cite ceva.

citeodata ii dau dreptate nevesti-mi ca ii e frica sa umble cu masina mica...

V-am ramas dator cu un link:

http://www.youtube.com/watch?v=qIQ2VI7pJ1o...feature=related

Pai nici un SUV nu te salveaza de un TIR asa ca discutia n-are rost. Ba din contra intr-o masina mica ai sansa sa treci pe sub el fara sa-l atingi .



Pai iei 100,000 de oameni si ii pui sa conduca 100,000km fiecare in masina respectiva. In tara si conditiile in care conduci tu. La sfirsit ii numeri si vezi iti au ramas. Repeti pentru celelalte masini si compari.
Altfel vorbim vorbe. De exemplu ce importanta are impactul frontal cu alta masina daca unde conduci tu accidentele prin impact frontal sint numai 10% din total? Sau invers, ce importanta au stelele daca 60% din accidente sint prin impact frontal? Sau prin rasturnare la "testul" elanului?

Da' de ce sa nu masor numarul total de victime ale accidentelor in care au fost implicate cele 100.000 masini pe distanta de 100.000km?

E adevarat ca siguranta inseamna si rezistenta la impact, dar nu uitati ca siguranta inseamna si stabilitate, franare , etc. As vrea sa vad eu daca "sta" pe drum un Q 7 mai bine ca "Micuta" mea?

peel car. si mai era si masina lui iustin capra. astea sint masini mici deja matizul e limuzina de lux pe linga ele.


Furia Neagra, masina lui lipoveanu vs ford. o sa caut si cu dodge-ul 2500 al lui oresti. asa e ca patrolul pare mic? si e destul de mare... acum vedeti si voi ce se intimpla cind se intilnesc un peel car si fordul si se pupa din dragoste...


This post has been edited by air_wolf: May 12 2009, 08:47 PM

Pai eu nu stiu daca Fordul ala are vreo sansa cu 100 de km la ora in vreo curba de 100 grade si nici daca poate frana la fel de repede ca o masina din clasa compacta . Si asta tine de siguranta. Accidentul poate fi si prevenit!