Ariane 6 : a strategic success for Europe, but challenges to come

The delays accu­mu­la­ted by Ariane 6 and the launch fai­lures of the Vega‑C light laun­cher had depri­ved Europe of auto­no­mous access to space, which is cru­cial to regai­ning its sove­rei­gn­ty. Lio­nel Suchet, inter­im CEO of the French Natio­nal Centre for Space Stu­dies (CNES), looks back on the suc­cess­ful launch of Ariane 6 in March 2025 and out­lines the pros­pects for the launch vehicles in Europe.

Lio­nel Suchet. This suc­cess fol­lows on from the mai­den flight of Ariane 6 in July 2024, which was alrea­dy a near-total suc­cess. The deor­bi­ting of the third stage, which could not be car­ried out during the first qua­li­fi­ca­tion flight, was suc­cess­ful­ly com­ple­ted in March 2025. This is a unique fea­ture of Ariane 6 com­pa­red to Ariane 5 : in line with sus­tai­nable deve­lop­ment prin­ciples, the upper stage is redi­rec­ted towards the atmos­phere to disintegrate.

The stakes were high for Europe. First­ly, because these flights, to which we can add the return to flight of Vega‑C, mark the return of full auto­no­my of access to space for the conti­nent. Second­ly, because Ariane 6’s first com­mer­cial flight enabled the launch of the CSO‑3 mili­ta­ry obser­va­tion satel­lite (Edi­tor’s note : the third and final satel­lite in the MUSIS pro­gramme, mar­king the com­ple­tion of the mili­ta­ry space capa­bi­li­ty rene­wal cycle pro­vi­ded for in the 2024–2030 mili­ta­ry pro­gram­ming law), at a time when the Pre­sident of the Repu­blic was dis­cus­sing Euro­pean sove­rei­gn­ty with his coun­ter­parts in Brussels.

Final­ly, from a com­mer­cial point of view, because Ariane 6’s order books are full, with cus­to­mers from both Europe and out­side Europe, par­ti­cu­lar­ly the Uni­ted States, who did not want to rely sole­ly on Spa­ceX. We have demons­tra­ted that Ariane 6 is a reliable part­ner at a cru­cial moment in the his­to­ry of inter­na­tio­nal com­pe­ti­tion in the space sector.

This is an extre­me­ly impor­tant issue, for obvious rea­sons rela­ting to cost and sus­tai­nable deve­lop­ment. We have been wor­king on it for seve­ral years through the Cal­lis­to and The­mis pro­jects, and today there are no lon­ger any major tech­no­lo­gi­cal chal­lenges to over­come. The first launches will take place very soon : first at low alti­tude next year, then lon­ger flights, until we achieve a reco­ve­rable flight by 2030. 

But we must bear in mind that it is not just a ques­tion of mas­te­ring the reu­sa­bi­li­ty of the laun­cher from a tech­no­lo­gi­cal point of view : it also requires a pro­found change in the way we manu­fac­ture them. Today, pro­duc­tion is sca­led to pro­duce a dozen Ariane 6 laun­chers per year. With the advent of a reu­sable laun­cher, the num­ber of laun­chers pro­du­ced each year will auto­ma­ti­cal­ly decrease. It is the­re­fore clear that the entire eco­no­mic and indus­trial model, as well as the entire lear­ning curve, will be impac­ted. Manu­fac­tu­rers are wor­king on this, and we are sup­por­ting them.

Europe, and France in par­ti­cu­lar, has excep­tio­nal resources, exper­tise and faci­li­ties, inclu­ding the CSG, which is uni­que­ly loca­ted. Its proxi­mi­ty to the equa­tor means that launches to the east can take full advan­tage of the sling­shot effect cau­sed by the Ear­th’s rota­tion. Its loca­tion on the Atlan­tic coast also means that rockets do not fly over land, and the­re­fore poten­tial resi­den­tial areas, when laun­ching north or east. The base is also pro­tec­ted from severe wea­ther phe­no­me­na such as cyclones. 

We the­re­fore have a very stra­te­gi­cal­ly loca­ted site. The moder­ni­sa­tion pro­grammes, which began two to three years ago and are due to be com­ple­ted in 2026, aim to make the base more ener­gy effi­cient, increase launch rates and enable the ope­ra­tion of dif­ferent laun­chers, inclu­ding Ariane 6 and Vega‑C, of course, but also reu­sable demons­tra­tors and mini and micro-laun­chers, such as the par­tial­ly reu­sable light laun­cher Maia, which is cur­rent­ly under deve­lop­ment. The goal is to make the centre a tru­ly mul­ti-laun­cher port.

The com­pa­ri­son is cer­tain­ly stri­king… Howe­ver, seve­ral fac­tors must be taken into account. First, we could consi­der increa­sing the launch rate, which is always a pos­si­bi­li­ty. But it is impor­tant to note that the Euro­pean and Ame­ri­can approaches to space are com­ple­te­ly dif­ferent. The Uni­ted States wants to occu­py the field in eve­ry sense of the word : set­ting foot on Mars, esta­bli­shing lunar bases, increa­sing the num­ber of satel­lites in orbit, pro­vi­ding com­mer­cial com­mu­ni­ca­tion ser­vices to the entire globe, etc. This is lea­ding in par­ti­cu­lar to Elon Musk’s mega-constel­la­tions. Let’s remem­ber that not so long ago, only 2,000 satel­lites were orbi­ting the Earth. Today, there are 9,000, inclu­ding 7,000 Star­link satel­lites, with plans to increase this num­ber to 40,000. Europe, meanw­hile, has a com­ple­te­ly dif­ferent approach to space deve­lop­ment, which it wants to be both ratio­nal and rea­so­nable. Mee­ting our needs in the coming years will the­re­fore involve deploying a few hun­dred satel­lites at most, in par­ti­cu­lar the IRIS² constel­la­tion, signed by the Euro­pean Com­mis­sion at the end of last year, which will com­prise 300 satel­lites. Euro­pean launch capa­bi­li­ties will be suf­fi­cient for this.

The use of nuclear power would contri­bute to our sove­rei­gn­ty in the space indus­try, as some appli­ca­tions can­not rely on solar panels alone, for example, per­ma­nent ins­tal­la­tions on the Moon or mis­sions to explore the dis­tant solar sys­tem. As both a major space power and a major nuclear power, France has the tech­no­lo­gi­cal and indus­trial capa­bi­li­ties to deve­lop both small sys­tems such as RHU (radioi­so­tope hea­ter units) and RTG (radioi­so­tope ther­moe­lec­tric gene­ra­tors) for pro­du­cing heat and elec­tri­ci­ty, and micro-power plants for pro­pel­ling hea­vy spa­ce­craft or for pro­du­cing ener­gy on a pos­sible future lunar base.

But other ques­tions arise. First­ly, there is the ques­tion of socie­tal accep­tance of such launches, given their loca­tion in French Guia­na, and second­ly, there is the bud­ge­ta­ry issue : the qua­li­fi­ca­tion of Kou­rou, but above all the deve­lop­ment of the sys­tems will require signi­fi­cant finan­cial invest­ment – seve­ral bil­lion euros for the micro power plants. We will the­re­fore need to seek to pool civil and mili­ta­ry appli­ca­tions as much as pos­sible, but also ter­res­trial and space applications.

How much prio­ri­ty should be given to this issue in the cur­rent context, which requires signi­fi­cant invest­ment on many fronts ? This is a ques­tion that poli­ti­cal deci­sion-makers will have to decide at Euro­pean level.

Interview by Anne Orliac